Semantic search
| Entered date | Event description | |
|---|---|---|
| ENS 55148 | 22 March 2021 13:16:00 | At 1005 EDT on 3/22/2021, the control room was notified of a personal medical event in the Radiologically Controlled Area. An ambulance entered Susquehanna plant property at 1019 and exited at 1028 to transport the individual to a local hospital. Ambulance did not enter the Protected Area. The individual was considered potentially contaminated since a complete frisk could not be performed prior to transport. Following transportation to a local hospital, Radiation Protection (RP) technicians confirmed the individual and ambulance were not contaminated. This event is reportable under 10CFR50.72(b)(3)(xii). An Event of Potential Public Interest (EPPI) was made to the Pennsylvania Emergency Management Agency (PEMA) due to an emergency vehicle accessing plant property. The NRC Resident Inspector was notified. |
| ENS 55128 | 9 March 2021 08:08:00 | At 0313 EST on March 9th, 2021, during performance of Unit 1 High Pressure Coolant Injection (HPCI) valve exercising, the inboard vacuum breaker isolation valve did not stroke closed as expected, but remained mid-position. The affected penetration of primary containment was isolated by closing the outboard HPCI vacuum breaker isolation valve. This results in an unplanned inoperability of the Unit 1 HPCI system. This is being reported as a loss of an entire safety function condition in accordance with 10CFR50.72(b)(3)(v)(D). The licensee notified the NRC Resident Inspector. Unit 1 is in a 14-day LCO for Tech Spec 3.5.1(d), HPCI inoperability. Tech Spec 3.6.1.3(a), Containment Penetration Valve, was completed with closing the outboard HPCI vacuum breaker isolation valve. The Units are in a normal offsite power line-up. |
| ENS 54078 | 22 May 2019 06:01:00 | On 5/22/2019, the 'A' Control Structure Chiller (Div I) tripped due to a loss of (motor control center) MCC 0B136. The 'B' Control Structure Chiller was already inoperable due to Div II (Emergency Service Water) ESW being out of service for planned maintenance. With the loss of Control Structure HVAC System the ability to maintain temperatures in various spaces including relay rooms, Control Room Floor Cooling and Emergency Switchgear rooms was lost. The 'B' Control Structure Chiller was restarted at 0251 EDT and cooling was reestablished to the required areas, however the 'B' chiller is not considered operable at this time. Units 1 and 2 entered (Technical Specification) TS 3.0.3 at 0256 EDT and a controlled shutdown of both units commenced, Unit 2 at 0340 EDT and Unit 1 0350 EDT. This constitutes a TS required shutdown and requires a 4 hour (Emergency Notification System) ENS notification in accordance with 10 CFR 50.72(b)(2)(i). The failure also requires an 8 hour ENS notification in accordance with 10 CFR 50.72(b)(3)(v) due to the loss of a safety function. The licensee needs to restore the 'B' loop of ESW to exit the Limiting Condition of Operation (LCO). The licensee is currently performing a flow surveillance, once complete and assuming the data is acceptable, the licensee will be able to exit the LCO. The units are in a normal electrical lineup. The licensee will be notifying the state of Pennsylvania FEMA Operations Center. The licensee has notified the NRC Resident Inspector.
On 5/22/2019 at 0601 EDT Susquehanna Steam Electric Station reported a shutdown had been commenced at 0340 EDT for Unit 2 and 0350 EDT for Unit 1 due to inoperability of both control structure chillers. Power has been restored to MCC 0B136, and at 0901 EDT the 'A' control structure chiller was declared operable and LCO 3.0.3 was exited. Power reduction for both units was halted at 0901 EDT and preparations for power restoration initiated. As of 1255 EDT on 5/22/2019, Unit 1 power is 94% and Unit 2 power is 92%. Notified the R1DO (Arner). |
| ENS 53256 | 12 March 2018 14:34:00 | A non-licensed supervisor tested positive for alcohol during pre-access screening. The individual's access to the plant was denied. The NRC Resident Inspector has been notified. |
| ENS 52795 | 8 June 2017 19:10:00 | At 1527 hrs (EDT) on June 8, 2017, Susquehanna Steam Electric Station Unit 1 reactor automatically scrammed due to a loss of Main Turbine Electro-Hydraulic Control (EHC) logic power causing a High Flux Reactor Power RPS (Reactor Protection System) trip. All control rods (fully) inserted and both reactor recirculation pumps tripped due to reaching reactor water level 2. Reactor water level lowered to -49 inches causing Level 3 (+13 inches) and Level 2 (-38 inches) isolations. HPCI (High Pressure Coolant Injection) and RCIC (Reactor Core Isolation Cooling) automatically initiated and were overridden by control room operators after RPV (Reactor Pressure Vessel) water level was restored to the normal band with feedwater. HPCI and RCIC injected to the Reactor Coolant System during reactor level stabilization. All isolations and initiations occurred as expected. No main steam relief valves opened. Pressure was controlled via main turbine bypass valve operation. All safety systems operated as expected. Secondary Containment Zone 1, 2, and 3 differential pressure lowered to 0 inch WG (Water Gauge) due to a trip of the Reactor Building Ventilation system that resulted from Unit 1 Level 2 isolation. Differential pressure was restored to Zones 1, 2, and 3 by the initiation of Standby Gas Treatment System on the Unit 1 Level 2 initiation. Unit 1 reactor is currently stable in Mode 3. Investigation into the loss of Main Turbine EHC logic power is underway. The NRC Resident Inspector has been notified. A voluntary notification to PEMA and press release will occur. The suspected cause of the loss of power to the EHC logic circuit is ongoing maintenance on the system. |
| ENS 52658 | 3 April 2017 11:37:00 | This is being reported under 10CFR20.1906(d)(1,2). At 1045 hours (EDT), the SSES (Susquehanna Steam Electric Station) Radwaste shipper was notified by the RP (Radiation Protection) shipping technician performing a receipt survey of an open transport vehicle shipped exclusive use carrying an empty radwaste liner exceeded the 10CFR71.47(b)(1) vehicle contact dose rates of 200 mR/hr. Per NDAP-QA-0720 (Nuclear Department Administrative Procedure) Attachment E, contaminated /radioactive shipments this is a 1 hour notification for exceeding the radiological receipt survey requirements of 200 mR/hr at any point on the outer surface of the vehicle. The vehicle was from Energy Solutions. The licensee will be using the vehicle to transport radwaste from the facility. The licensee has notified the Pennsylvania Emergency Management Agency and the NRC Resident Inspector. |
| ENS 52599 | 8 March 2017 08:49:00 | On March 08, 2017 at 0239 hours (EST), Secondary Containment Zone 3 (Unit 1 and 2 Reactor Building) differential pressure lowered to 0 (inches) WG due to a trip of the running Zone 3 Secondary Containment fans. The fan trip was caused by a human performance error during a Unit 2 outage related activity. Required differential pressure per SR 3.6.4.1.1 could not be maintained. Zone 3 differential pressure recovered to (greater than) 0.25 (inches) WG at 0255 hours after restart of Zone 3 Secondary Containment fans. All other Zones of Secondary Containment were unaffected by this event. This event is being reported under 10 CFR 50.72(b)(3)(v)(C) and per the guidance of NUREG 1022 Rev. 3 section 3.2.7 as a loss of a Safety Function. There is no redundant Susquehanna Secondary Containment System. The licensee informed the NRC Resident Inspector. |
| ENS 52266 | 27 September 2016 22:27:00 | On September 27, 2016 at 1644 (EDT), damaged ductwork was identified in the secondary containment boundary associated with reactor building zone 3 (Units 1 and 2) recirculation plenum. The size of the hole in the secondary containment boundary was determined to be 22.5 square inches. Due to exceeding allowable total leakage in the current secondary containment isolation configuration, a violation of SR 3.6.4.1.5 (occurred). Action to establish a tested configuration with sufficient inleakage margin to restore compliance with SR 3.6.4.1.5 was completed September 27, 2016 at 2115 hrs. This event is being reported under 10 CFR 50.72(b)(3)(v)(C) and per the guidance of NUREG 1022, Rev 3, Section 3.2.7 as a loss of a Safety Function. There is no redundant Susquehanna Secondary Containment System. The licensee notified the NRC Resident Inspector.
Following the 8 hour 10 CFR 50.72 notification made on September 27, 2016 (EN 52266), further engineering analysis determined that the as-found tear in the Zone 3 ductwork did not impact the ability of Secondary Containment to perform its safety function and that Secondary Containment was not inoperable as a result of the condition. To support the determination, a drawdown test was conducted in a limiting configuration (i.e. least inleakage margin). No substantial change in drawdown testing results were observed over the last three tests. These tests spanned over seven years. Additionally, repairs were promptly made to the affected area. As a result, this event notification is being retracted as it is not reportable pursuant to 10 CFR 50.72(b)(3)(v)(C). The licensee notified the NRC Resident Inspector. Notified the R1DO (Dwyer). |
| ENS 51750 | 22 February 2016 18:47:00 | On February 22, 2016 at 1345 (EST). Secondary Containment became inoperable due to failure to meet a Surveillance Requirement (SR 3.6.4.1.3) on Unit 1. The inoperability was caused when Unit 1 Reactor Building Airlock doors were inadvertently opened simultaneously. Secondary Containment was restored February 22, 2016 at 1346 when the doors were closed. This event is being reported under 10 CFR 50.72(b)(3)(v)(C) and per the guidance of NUREG 1022, Rev. 3 section 3.2.7 as a loss of a Safety Function. There is no redundant Susquehanna Secondary Containment system. The licensee informed the NRC Resident Inspector. |
| ENS 51588 | 6 December 2015 09:58:00 | On December 06, 2015 at 0546 (EST), Reactor Building Zone 1 Secondary Containment differential pressure lowered to less than 0.25 inch Water Column (WC) (degrading vacuum) when the running Reactor Building Zone 1 exhaust fan tripped. This required a TS 3.6.4.1 entry for failure to meet SR 3.6.4.1.1 on Unit 1 and Unit 2. The standby fan automatically started, restoring of Reactor Building Zone 1 Secondary Containment differential pressure to greater than -0.25 inch WC. Field operators confirmed proper system response at 0553 (EST) December 06, 2015. This event is being reported under 10 CFR 50.72(b)(3)(v)(c) and per the guidance of NUREG 1022 Rev 3 section 3.2.7 as a loss of a Safety Function. " The licensee has notified the NRC Resident Inspector. |
| ENS 50690 | 17 December 2014 15:07:00 | This report is made due to notification from PPL Susquehanna to Pennsylvania Department of Environmental Protection (DEP) regarding a sewerage leak at the plant property. The notification was made at 1335 EST hours on 12/17/14. During a routine inspection by a contractor who performs checks for PPL Susquehanna, an area was identified as a potential leak location. When the sewerage grinder pump was run, there was visible evidence in the soil that a leak existed. Extent and duration of the leak is not know at this time. This event requires notification to Pennsylvania DEP. The licensee has notified the NRC Resident Inspector. |
| ENS 50595 | 5 November 2014 17:17:00 | On November 5, 2014 at 1115 (EST), Secondary Containment Zone 3 (Unit 1 & 2 Reactor Building) was unintentionally crosstied to Secondary Containment Zone 2 (Unit 2 Reactor Building) for several seconds during passage of personnel through a personnel airlock. Secondary Containment Zone 2 & Zone 3 ventilation remained in service and stable. LCO 3.6.4.1 was entered and exited based on the prohibited crosstie of Secondary Containment Zones. Tech Spec Secondary Containment Operability requires that at least one door remain closed for airlocks where two doors are provided when an access opening between Secondary Containment Zones is being used for exit and entry. This event is being reported under 10 CFR 50.72(b)(3)(v)(C) and per the guidance of NUREG 1022 Rev. 3 section 3.2.7 as a loss of a Safety Function. There is no redundant Susquehanna Secondary Containment System. The licensee has notified the NRC Resident Inspector. |
| ENS 49613 | 6 December 2013 17:52:00 | At 1248 EST, Unit 2 High Pressure Coolant Injection (HPCI) system was being tested for routine quarterly flow verification using surveillance test procedure SO-252-002. When HPCI turbine speed was lowered to approximately 2400 RPM, oscillations on turbine speed, flow and discharge pressure were observed. HPCI turbine speed was raised to approximately 2700 RPM and the oscillations stopped. Unit 2 HPCI system had been declared inoperable and LCO 3.5.1 entered at 1200 EST for the surveillance test. (This is a 14 day LCO.) Review by Engineering determined that cause of the oscillations warrant further evaluation and HPCI remains inoperable. HPCI is a single train Emergency Core Cooling Safety system. This event results in the loss of an entire safety function which requires an 8 hour ENS notification in accordance with 10CFR50.72(b)(3)(v). There are no other ECCS systems presently out of service. The licensee notified the NRC Resident Inspector.
NUREG-1022, Revision 3, states, 'if the retraction or cancellation of a report under this criterion is due to a revised operability determination, the retraction or cancellation should discuss the basis for why the operability determination was revised, and why it is believed that system operability was never lost (i.e., in lieu of the initial determination).' As indicated in the initial report, Engineering determined that the cause of the oscillations required further evaluation and HPCI remained inoperable. Additional evaluation by Engineering resulted in a conclusion that HPCI was OPERABLE with the observed oscillations at the low flow conditions. Details are as follows: HPCI speed/flow oscillations at low flow conditions can occur due to inherent instability at these conditions. This phenomenon is understood and documented in industry OE (Operating Experience), EPRI (Electric Power Research Institute) maintenance guidelines, and station procedures. HPCI system operation and control during the surveillance were as expected and demonstrated proper response and stable operation, with the only exception being the described oscillations at the low flow condition. This was confirmed by a review of the system response on the start-up traces. A system walkdown confirmed no abnormality with the control system equipment or governor setting. No tuning adjustments were considered to be necessary based on the low magnitude of the oscillations and their negligible impact on system operation. Unit 2 HPCI was declared OPERABLE and LCO 3.5.1 was cleared at 2308 (EST) on December 6, 2013. Based on the above additional information, PPL (Pennsylvania Power and Light) is retracting this report. The licensee has notified the NRC Resident Inspector. Notified the R1DO (Rogge). |
| ENS 49465 | 23 October 2013 10:20:00 | On October 23, 2013 at 0620, Susquehanna Steam Electric Station operators observed secondary containment differential pressure was at negative 0.17 inches water gauge for Zone II (Unit 2 Reactor Building). Tech Spec Secondary Containment Operability requires a negative pressure of at least 0.25 inches water gauge. Zone I (Unit 1 Reactor Building) and III (Common Refuel Floor Area) ventilation remained in service and stable. Zone II differential pressure was restored to within the required band by manual damper adjustment in about 15 minutes and was verified to be stable. LCO 3.6.4.1 was entered for both units at 0620 and exited at 0635. This event is being reported under 10 CFR 50.72(b)(3)(v) and per the guidance of NUREG 1022 Rev 3 section 3.2.7 as a loss of a Safety Function. There is no redundant Susquehanna Secondary Containment System. The licensee has notified the NRC Resident Inspector. |
| ENS 48777 | 22 February 2013 20:13:00 | On February 22, 2013 at approximately 1430 (EST), Susquehanna identified a computer program error that affected the Susquehanna Fitness for Duty (FFD) program. Specifically, two Behavioral Observation Program (BOP) inquiries were accepted without proper documentation of the required need to continue unescorted access authorization (UAA) and without verification of an actual observation within the required thirty day timeframe. The computer error resulted in answers for two of the three questions on the Behavior Observation Inquiry form not being recorded when the form was submitted by the supervisor. This resulted in the two security accounts being re-zeroed and allowing UAA for an additional 15 days. The BOP supervisor was contacted and verified that these individuals were intended to continue with UAA. At no time were these individuals removed from the FFD or Behavior Observation Program. In accordance with 10 CFR 26.719(b)(4), this report is being made based on being a potential programmatic failure, degradation, or discovered vulnerability of the FFD program that may permit undetected drug or alcohol use or abuse by individuals within a protected area, or by individuals who are assigned to perform duties that require them to be subject to the FFD program. The (NRC Resident Inspector) and the Branch Chief for the Region I Division of Reactor Safety were notified. |
| ENS 48540 | 27 November 2012 18:40:00 | At 1720 hours on November 27, 2012 PPL SSES (Susquehanna Steam Electric Station) notified the Occupational Safety and Health Administration that an employee had suffered a fatality. On November 27, 2012 at 1313 hours, a PPL employee suffered an apparent heart attack while at the Luzerne County Community College (LCCC) Public Safety Training Institute while performing SCBA (Self Contained Breathing Apparatus) training. The employee was transported to the Geisinger Wyoming Valley hospital and pronounced dead. PPL was notified at 1432 of the fatality. The LCCC training facility is not located on PPL owned property. This ENS report is being made in accordance with 50.72(b)(2)(xi). The NRC Resident Inspector was notified. The licensee has also notified the Commonwealth. |
| ENS 48055 | 28 June 2012 20:44:00 | At 1353 EDT on 06/28/2012, Susquehanna Steam Electric Station experienced a loss of power from one of two offsite power sources when transformer 20 shutdown automatically. All ESS (Engineered Safeguards System) electrical busses fed by this transformer automatically transferred to the other offsite power source (transformer 10). Additionally, startup bus 20, which is normally fed from transformer 20, automatically transferred to transformer 10. On each unit, multiple system containment isolation valves closed as a result of the electrical transient. Operators were able to reset and restore each system. On unit one, residual heat removal (RHR) shutdown cooling ceased operation during the transient. Shutdown cooling was restored within one hour by control room operators in accordance with off-normal procedures. Unit two remained at 100% power throughout the event. This incident is being reported as an unplanned actuation of systems that mitigate the consequences of significant events per 10 CFR 50.72(b)(3)(iv)(A). The licensee is in a 72 hour LCO on Unit 2 as a result of the loss of offsite power. All emergency diesels generators are available. The licensee is investigating the cause of the transformer 20 shutdown. The NRC Resident Inspector and the Pennsylvania Emergency Management Agency (PEMA) have been notified. |
| ENS 46644 | 25 February 2011 23:12:00 | At 2027 EST, Unit 1 HPCI system was declared inoperable due to a steam leak on HV155F002, HPCI Steam Supply Inboard Isolation Valve. Engineering evaluation determined that the valve actuator will not close the valve fully under design basis conditions, due to the impingement of steam from the valve packing region on the valve stem. The penetration flow path has been isolated and the outboard isolation valve has been deactivated. HPCI is a single train ECCS safety system, This event results in the loss of an entire safety function which requires an 8 hour ENS notification in accordance with 10CFR50.72(b)(3)(v) and the guidance provided under NUREG-1022, rev. 2. There are no other ECCS systems presently out of service. Unit 1 is in a 14 day LCO 3.5.1. EDG's are operable, and offsite power is normal. There is no increase in plant risk, and the licensee will notify the Pennsylvania Emergency Management Agency (PEMA). The NRC Resident Inspector has been notified. |
| ENS 45866 | 22 April 2010 13:20:00 | At 10:51 on 4/22/10, Susquehanna Unit 1 experienced an automatic reactor SCRAM on reactor low level, +13", during the initial testing of the Feedwater Integrated Control System. Following the SCRAM, reactor water level dropped to approx. -30", and the Reactor Core Isolation Cooling system initiated and injected into the vessel. Level was recovered by the Feedwater System and the RCIC system. Division 2 Alternate Rod Insertion unexpectedly initiated during the level transient. Due to scheduled maintenance activities, the 11B Aux Bus did not transfer to the off site power supply post SCRAM. The 11B Aux bus was restored at 12:17. There were no ECCS initiations and no challenges to containment. This event is a Reactor Protection System (RPS) actuation when the reactor is critical, and is reportable as a four hour ENS Notification under 10 CFR 50.72(b)(2)(iv)(B). This event is also an unplanned actuation of a system used to mitigate the consequences of a significant event and is reportable as an eight hour ENS notification under 10CFR50.72(b)(3)(iv)(A). The scram was described as uncomplicated. All rods fully inserted and all systems functioned as required. The initiation of the alternative rod insertion should not occur unless level drops below -38" but the initiation did not result in any complications. The offsite supply breaker to Aux bus 11B was under maintenance when the scram occurred and so the loss of power was expected. This bus supplies some balance of plant loads which were lost (recirculation pump, condensate pump, and circulating water pump) but the loss of these components had no impact on the transient. The NRC Resident Inspector has been notified. The licensee will notify State authorities and also plans a press release. |