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 Entered dateSiteRegionReactor typeSystemScramEvent description
ENS 548164 August 2020 22:43:00MillstoneNRC Region 1Service water

EN Revision Text: BOTH SERVICE WATER HEADERS DECLARED INOPERABLE On 8/4/20, at 1745 EDT, Millstone Unit 2 entered technical specification (TS) 3.0.3 due to both service water headers being declared inoperable because strainer differential pressures (D/Ps) were greater than 9 psid. The high service water strainer D/P was the result of heavy debris impingement caused by tropical storm Isaias. To reduce heat loads and service water flow, Unit 2 reduced power to 75 percent. One service water header was restored to operable at 1816 EDT, at which time TS 3.0.3 was exited. At 1843 EDT both service water headers were declared operable. The NRC Resident Inspector has been notified.

  • * * RETRACTION ON 8/19/2020 AT 1141 EDT FROM ERIC DONCH TO KIRBY SCALES * * *

The purpose of this call is to retract a report made on August 4, 2020, NRC Event Number EN 54816 describes a condition at Millstone Power Station Unit 2 (MPS2) in which both trains of service headers were declared inoperable due to service water strainer differential pressures greater than 9 psid. The condition was reported to the NRC pursuant to 10 CFR 50.72(b)(3)(v)(A), (B) and (D) via an 8 hour prompt report as an event or condition that at the time of discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to shutdown the reactor and maintain it in a safe shutdown condition, remove residual heat and mitigate the consequences of an accident. Upon further review, MPS2 determined that there was no loss of safety function. An engineering evaluation supports the conclusion that a strainer differential pressure of 16 psid would not challenge the system flow distribution during worst case conditions. The evaluation also demonstrates that flowrates on both headers were observed to be unaffected during the timeframe of the high strainer differential pressure conditions. Therefore, both service water headers would have provided the required flows to perform their safety function. Therefore, this condition is not reportable and NRC Event Number EN 54816 is being retracted. The basis for this conclusion has been provided to the NRC Resident Inspector. Notified R1DO (Greives).

ENS 548123 August 2020 23:31:00BrunswickNRC Region 2High Pressure Coolant Injection
Reactor Protection System
Emergency Diesel Generator
Main Steam Isolation Valve
Primary Containment Isolation System
Reactor Core Isolation Cooling
Shutdown Cooling
Fuel Pool Cooling and Cleanup

At 2312 EDT, on August 4, 2020, Brunswick Unit 1 declared an Unusual Event due to a loss of offsite power. The unit was at approximately 20 percent power and was not synced to the grid when the unit automatically scrammed. All control rods fully inserted. Emergency Diesel Generators started and began powering the safety buses. Safety systems actuated as expected. The Unit also experienced a loss of Fuel Pool Cooling and Cleanup System, but one pump was returned to service. Unit 2 remains at 100 percent power and is unaffected. The licensee notified State and local governments, as well as the NRC Resident Inspector. Notified DHS SWO, FEMA Operations Center, CISA IOCC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email).

  • * * UPDATE FROM MARK TURKAL TO DONALD NORWOOD AT 0120 EDT ON 8/4/2020 * * *

At approximately 2302 EDT, a loss of offsite power occurred on Unit 1. This resulted in a Reactor Protection System (RPS) actuation. Per design, emergency diesel generators 1 and 2 properly started and loaded to their respective emergency buses. The Reactor Core Isolation Cooling (RCIC) system was manually started and is being used to control reactor water level. The High Pressure Coolant Injection (HPCI) system was manually started and is being used for pressure control. As previously reported, an Unusual Event was declared at 2312 EDT due to the loss of offsite power. At the time of the event, Unit 1 was in the process of shutting down for maintenance associated with a ground on the main generator. Due to the RPS actuation while critical, this event is being reported as a four-hour, nonemergency notification per 10 CFR 50.72(b)(2)(iv)(B). As a result of the reactor trip, reactor water level reached low level 1 (LL1). The LL1 signal causes a Group 2 (i.e., floor and equipment drain isolation valves), Group 6 (i.e., monitoring and sample isolation valves) and Group 8 (i.e., shutdown cooling isolation valves) isolations. The LL1 isolations occurred as designed; the Group 8 valves were closed at the time of the event. Per design, the loss of offsite power also caused a Group 1 (i.e., main steam isolation valve) isolations. Due to the Emergency Diesel Generator and Primary Containment Isolation System (PCIS) actuations, this event is also being reported as an eight-hour, nonemergency notification in accordance with 10 CFR 50.72(b)(3)(iv)(A). Unit 2 was not affected. There was no impact to the health and safety of the public or plant personnel. The safety significance of the event is minimal. All safety related systems operated as designed. Investigation of the cause of the loss of offsite power is in progress. The licensee notified the NRC Resident Inspector. Notified R2DO (Inverso).

ENS 5480831 July 2020 17:40:00Saint LucieNRC Region 2

A Hurricane Warning is in effect for St. Lucie County including the plant site. A Hurricane Warning was confirmed with the State Watch Office at 1700 EDT. As a mater of procedure, St. Lucie Nuclear Power Plant entered an Unusual Event classification for the Hurricane Warning. State and local officials have been notified by the licensee. The NRC Resident Inspector was notified by the licensee. This report is submitted in accordance with 10 CFR 50.72(a)(1)(i) due to the Notice of Unusual Event and 10 CFR 50.72(b)(2)(xi) due to the Offsite Notification." Notified DHS SWO, FEMA OC, DHS NICC WO, CISA IOCC (email), DHS SWO (email); FEMA NWC (email), FEMA Ops Center (email), FEMA-NRCC-sasc (email), NRCC THD Desk (email), NuclearSSA (email).

  • * * UPDATE ON 8/2/20 AT 1456 EDT FROM LOUIS ENGELKE TO BETHANY CECERE * * *

The Hurricane Warning was downgraded to a Tropical Storm Warning by the National Weather Service for St. Lucie County, including the plant site. At time 1445 EDT, on 08/02/20, St. Lucie Nuclear Plant has terminated from the Unusual Event classification. There are no changes in plant status for either unit. Both units are stable at 100% power. The NRC Resident Inspector was notified of this by the licensee. The licensee notified State and County officials of the termination." Notified R2DO (M. Miller), IRD MOC (Kennedy), NRR EO (C. Miller), DHS SWO, FEMA OC, DHS NICC WO, CISA IOCC (email), DHS SWO (email); FEMA NWC (email), FEMA Ops Center (email), FEMA-NRCC-sasc (email), NRCC THD Desk (email), NuclearSSA (email)

ENS 5480630 July 2020 11:59:00CallawayNRC Region 4

EN Revision Text: EMERGENCY PROCEDURE ERROR POTENTIALLY PREVENTING TIMELY COMPLETION OF EMERGENCY CORE COOLING SYSTEM RECIRCULATION ALIGNMENT At 0815 CDT on 7/30/2020, it was determined that a procedural error in emergency procedure ES1.3, Transfer to Cold Leg Recirculation, could delay realignment from emergency core cooling system (ECCS) injection phase to recirculation phase under lower plant operational modes. It is noted this scenario is postulated to occur only when the boron dilution mitigation system is operable in lower modes of operation as per Technical Specification 3.3.9 (required operable in Mode 2 (below P-6), 3, 4 and 5). Current plant conditions require this feature nonfunctional so this issue does not impact current plant conditions. This condition is not bounded by existing design and licensing documents; however, it poses no current impact to the health and safety of the public or plant personnel. Therefore, this event is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(ii)(B).

The NRC Resident Inspector has been notified.

  • * * RETRACTION ON 8/17/2020 AT 1603 EDT FROM JOSH COPELAND TO KERBY SCALES * * *

Event Notification (EN) 54806, made on 7/30/2020, is being retracted because re-evaluation performed subsequent to the notification has demonstrated that the error in Emergency Operating Procedure ES1.3 would not have resulted in a condition outside of the current licensing basis analyses of record for the Callaway Plant. This re-evaluation addressed core effects, containment pressure-temperature and radiological consequences analyses, documented in the plant's corrective action program. The re-evaluation has led to the conclusion that the procedural error in ES1.3 would not have prevented any system required to be OPERABLE by the Technical Specifications from performing its specified safety functions. With all systems capable of performing their specified safety functions, the current licensing basis analyses of record for Callaway Plant remain valid and bounding. Based on these considerations, it has been determined that the condition reported in EN 54806 did not result in the plant being in an unanalyzed condition that significantly degraded plant safety. Consequently the condition did not meet the criteria for an 8-hour notification per 10 CFR 50.72(b)(3)(ii)(B) for an unanalyzed condition that significantly degrades safety. The NRC Resident Inspector has been notified of this Event Notification retraction. Notified R4DO (Taylor)

ENS 5480329 July 2020 04:28:00Prairie IslandNRC Region 3Radiation monitor RE-69, 'Guardhouse Area Radiation Detector' was found failed on operator rounds. RE-69 is a category A1 piece of equipment that provides the sole means of indication for a parameter used to directly assess emergency action level (EAL) RA3.1, 'dose rate greater than 15 mR/hr in either of the following areas: Control Room (R-1), Central Alarm Station (R-69).' A compensatory measure was subsequently established and the ability to assess EAL RA3.1 has been restored. There was no impact on the health and safety of the public or plant personnel. The NRC Senior Resident Inspector has been notified.
ENS 5480024 July 2020 09:00:00SequoyahNRC Region 2At 0105 (EDT) on 7/24/20 it was discovered Unit 2 Ice Bed was INOPERABLE. Therefore, since this is a single train system the requirements of 50.72 (b)(3)(v)(C) and (D) have been met. This condition is being reported as an 8-hour non-emergency NRC Notification. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. This condition put the unit in a 48-hour LCO. The old chillers were put into service to bring the temperature of the ICE bed down. At 0833 EDT, the technical specification limit was no longer exceeded and the unit exited the LCO.
ENS 5479621 July 2020 12:42:00RobinsonNRC Region 2At 0851 EDT on July 21, 2020, a Technical Specification required shutdown was initiated at Robinson Unit 2. Technical Specification LCO 3.0.3 was entered due to LCO 3.1.7 not being met as a result of indication loss on Control Rod positions with more than one position indication inoperable for a group. LCO 3.0.3 was entered at 0752 EDT to initiate action within 1 hour to place the unit in MODE 3 within 7 hours. Since a Technical Specification required shutdown was initiated, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(i). Technical Specification LCO 3.0.3 was exited at 1003 EDT on July 21, 2020. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. Shutdown was initiated and power was reduced approximately 3 percent. Reactor power was back to 98.5 percent at the time of notification.
ENS 5479521 July 2020 08:58:00Browns FerryNRC Region 2Reactor Protection System
Main Steam Isolation Valve
Primary Containment Isolation System
Main Condenser
Manual ScramThe following was received from TVA - Brown's Ferry at 0858, 21 July 20. On July 21, 2020, at 0435 hours Central Daylight Time, Browns Ferry Unit 1 inserted a manual reactor scram due to degrading main condenser vacuum from marine biofouling at the intake structure. Browns Ferry Unit 2 is in Mode 4 and Browns Ferry Unit 3 is at approximately 76% rated thermal power and stable. Primary Containment Isolation Systems received an actuation signal for groups 2, 3, 6, 8 on reactor water level below +2". All Primary Containment Isolation System groups that received an actuation signal performed as designed. Additionally, all other systems functioned as designed. This event is reportable within 4 hours per 10CFR50.72(b)(2)(iv)(B) - Any event or condition that results in actuation of the reactor protection system (RPS) when the reactor is critical except when the actuation results from and is part of a pre-planned sequence during testing or reactor operation. This event also requires an 8 hour report per 10CFR50.72(b )(3)(iv)(A), Any event or condition that results in valid actuation of any of the systems listed in paragraph (b)(3)(iv)(B), (1) Reactor protection system (RPS) including: reactor scram or reactor trip, except when the actuation results from and is part of a pre-planned sequence during testing or reactor operation and (2) General containment isolation signals affecting containment isolation valves in more than one system or multiple main steam isolation valves (MSIVs). The NRC Resident Inspector has been notified." The plant is stable in Mode 3 and will remain shutdown until marine growth clogging the intake structure abates.
ENS 5479420 July 2020 18:11:00Browns FerryNRC Region 2Feedwater
Reactor Protection System
Main Steam Isolation Valve
Primary containment
Main Condenser
Manual Scram

On July 20, 2020, at 1325 hours Central Daylight Time, Brown's Ferry Unit 2 inserted a manual reactor scram due to degrading main condenser vacuum from marine biofouling at the intake structure. Brown's Ferry Unit 1 performed a down power to 43% and Unit 3 down powered to 76%. Conditions are stable on both Unit 1 and 3 following unit down power.

Primary Containment Isolations Systems received an actuation signal for groups 2, 3, 6, and 8 on reactor water level below +2". All Primary Containment Isolations System groups that received an actuation signal performed as designed. Additionally, all other systems functioned as designed. This event is reportable within 4 hours per 10CFR50.72(b)(2)(iv)(B) - Any event or condition that results in actuation of the reactor protection system (RPS) when the reactor is critical except when the actuation results from and is part of a pre-planned sequence during testing or reactor operation.

This event also requires an 8 hour report per 10CFR 50.72(b)(3)(iv)(A), "Any event or condition that results in valid actuation of any of the systems listed in paragraph (b)(3)(iv)(B), (1) Reactor protection system (RPS) including: reactor scram or reactor trip, except when the actuation results from and is part of a pre-planned sequence during testing or reactor operation and (2) General containment isolation signals affecting containment isolation valves in more than one system or multiple main steam isolation valves (MSIVs). The NRC Resident Inspector has been notified. All control rods fully inserted and decay heat is being removed via normal feedwater and condenser.

ENS 5479220 July 2020 16:36:00Davis BesseNRC Region 3

In the evening of 7/19/20, a report was received from Ottawa County Sheriff Dispatch personnel that a single siren had sounded. Review of the siren system computer log determined Siren 202 in Carroll Township had malfunctioned and sounded at approximately 2003 EDT, and sounded a second time at approximately 2045 EDT while the siren was being polled for troubleshooting. Personnel were dispatched to Siren 202 to deenergize both the AC and DC power to prevent additional soundings. The cause of the siren sounding is under review, but it occurred following storms passing through the area. This notification is being made solely as a four-hour, non-emergency notification for a Notification of Other Government Agency. This event is reportable in accordance with 10 CFR 50.72(b)(2)(xi).

There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.

ENS 5478917 July 2020 19:59:00Diablo CanyonNRC Region 4Reactor Protection System
Auxiliary Feedwater
Manual ScramOn July 17, 2020, at 1346 PDT with Diablo Canyon Power Plant Unit 2 operating at 100 percent power, the reactor was manually tripped in accordance with plant procedures due to increasing hydrogen usage in the Unit 2 main generator. The reactor trip was uncomplicated and the Auxiliary Feedwater system started as expected. The plant is stable in Mode 3. This notification is being made in accordance the requirements of 10 CFR 50.72(b)(2)(iv)(B) as a manual actuation of the reactor protection system and 10 CFR 50.72(b)(3)(iv)(A) as an automatic actuation of a specified safety system. The cause of the increased hydrogen usage is under investigation. There was no impact to the health and safety of the public or plant personnel. The Senior Resident Inspector has been notified.
ENS 5478115 July 2020 14:58:00Watts BarNRC Region 2At 0835 EDT on July 15, 2020, it was discovered that the main control room (MCR) envelope was inoperable due to a MCR door being found ajar; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v). The door was closed, restoring the MCR envelope to operable at 0839 EDT. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
ENS 5477613 July 2020 17:10:00VogtleNRC Region 2On July 13, 2020 at 0831 (EDT), Southern Nuclear Operating Company (SNC) determined an SNC supervisory personnel failed their fitness for duty test. The employee has been removed from the site and their access has been terminated. The NRC Resident Inspector has been notified.
ENS 5477310 July 2020 08:30:00HarrisNRC Region 2At 900 EDT on July 10, 2020, Duke Energy will undertake planned maintenance activities on the common Emergency Operations Facility (EOF) for Brunswick, Catawba, Harris, McGuire, Oconee, and Robinson Nuclear Sites. The work includes performance of upgrades to the emergency AC power system and requires the removal of both normal and emergency power to the facility. The work duration is approximately ten (10) days. If a declared emergency were to occur at Harris Nuclear Plant, the Alternate EOF would be set up in the McGuire Alternate Technical Support Center (TSC) location as described in implementing procedures. The Emergency Response Organization has been notified that the primary EOF will be unavailable during the upgrade project and to report to the alternate location, if activated. This is an eight-hour, non-emergency notification for a loss of Emergency Assessment Capability. This event is reportable in accordance with 10 CFR 50.72(b)(3)(xiii) because the work activity affects the functionality of an emergency response facility. The Resident Inspector has been notified.
ENS 5477210 July 2020 08:28:00BrunswickNRC Region 2At 0900 EDT hours on 7/10/2020 Duke Energy will undertake planned maintenance activities on the common Emergency Operations Facility (EOF) for Brunswick, Catawba, Harris, McGuire, Oconee, and Robinson nuclear sites. The work includes performance of upgrades to the emergency AC power system and requires the removal of both normal and emergency power to the facility. The work duration is approximately ten (10) days. If a declared emergency were to occur at Brunswick, the Alternate EOF would be set up in the Catawba Alternate Technical Support Center (TSC) location as described in implementing procedures. The Emergency Response Organization has been notified that the primary EOF will be unavailable during the upgrade project and to report to the alternate location, if activated. This is an eight-hour, non-emergency notification for a loss of emergency assessment capability. This event is reportable in accordance with 10 CFR 50.72(b)(3)(xiii) because the work activity affects the functionality of an emergency response facility. The NRC Resident Inspector has been notified.
ENS 5477110 July 2020 08:17:00OconeeNRC Region 2At 0900 EDT hours on 7/10/2020 Duke Energy will undertake planned maintenance activities on the common Emergency Operations Facility (EOF) for Brunswick, Catawba, Harris, McGuire, Oconee, and Robinson nuclear sites. The work includes performance of upgrades to the emergency AC power system and requires the removal of both normal and emergency power to the facility. The work duration is approximately ten (10) days. If a declared emergency were to occur at Oconee, the Alternate EOF would be set up in the Catawba Alternate Technical Support Center (TSC) location as described in implementing procedures. The Emergency Response Organization has been notified that the primary EOF will be unavailable during the upgrade project and to report to the alternate location, if activated. This is an eight-hour, non-emergency notification for a loss of emergency assessment capability. This event is reportable in accordance with 10 CFR 50.72(b)(3)(xiii) because the work activity affects the functionality of an emergency response facility. The NRC Resident Inspector has been notified.
ENS 5477010 July 2020 08:01:00CatawbaNRC Region 2

At 0900 EDT hours on 7/10/2020 Duke Energy will undertake planned maintenance activities on the common Emergency Operations Facility (EOF) for Brunswick, Catawba, Harris, McGuire, Oconee, and Robinson nuclear sites. The work includes performance of upgrades to the emergency AC power system and requires the removal of both normal and emergency power to the facility. The work duration is approximately ten (10) days.

If a declared emergency were to occur at Catawba, the Alternate EOF would be set up in the McGuire Alternate Technical Support Center (TSC) location as described in implementing procedures. The Emergency Response Organization has been notified that the primary EOF will be unavailable during the upgrade project and to report to the alternate location, if activated.

This is an eight-hour, non-emergency notification for a loss of emergency assessment capability. This event is reportable in accordance with 10 CFR 50.72(b)(3)(xiii) because the work activity affects the functionality of an emergency response facility. The NRC Resident Inspector has been notified.

ENS 5476910 July 2020 07:45:00McGuireNRC Region 2At 0900 EDT hours on 7/10/2020 Duke Energy will undertake planned maintenance activities on the common Emergency Operations Facility (EOF) for Brunswick, Catawba, Harris, McGuire, Oconee, and Robinson nuclear sites. The work includes performance of upgrades to the emergency AC power system and requires the removal of both normal and emergency power to the facility. The work duration is approximately ten (10) days. If a declared emergency were to occur at McGuire, the Alternate EOF would be set up in the Catawba Alternate Technical Support Center (TSC) location as described in implementing procedures. The Emergency Response Organization has been notified that the primary EOF will be unavailable during the upgrade project and to report to the alternate location, if activated. This is an eight-hour, non-emergency notification for a loss of emergency assessment capability. This event is reportable in accordance with 10 CFR 50.72(b)(3)(xiii) because the work activity affects the functionality of an emergency response facility. The NRC Resident Inspector has been notified.
ENS 5476810 July 2020 07:10:00RobinsonNRC Region 2

At 0900 EDT hours on 7/10/2020 Duke Energy will undertake planned maintenance activities on the common Emergency Operations Facility (EOF) for Brunswick, Catawba, Harris, McGuire, Oconee, and Robinson nuclear sites. The work includes performance of upgrades to the emergency AC power system and requires the removal of both normal and emergency power to the facility. The work duration is approximately ten (10) days.

If a declared emergency were to occur at Robinson, the Alternate EOF would be set up in the Catawba Alternate Technical Support Center (TSC) location as described in implementing procedures. The Emergency Response Organization has been notified that the primary EOF will be unavailable during the upgrade project and to report to the alternate location, if activated.

This is an eight-hour, non-emergency notification for a loss of emergency assessment capability. This event is reportable in accordance with 10 CFR 50.72(b)(3)(xiii) because the work activity affects the functionality of an emergency response facility. The NRC Resident Inspector has been notified.

ENS 547625 July 2020 23:05:00Turkey PointNRC Region 2Auxiliary FeedwaterReactor trip caused by turbine trip due to voltage regulator issues. Plant is stable. Exited the Emergency Operating Procedure Network. Auxiliary Feedwater automatically actuated and was subsequently restored to standby. The licensee notified the NRC Resident Inspector.
ENS 547612 July 2020 02:01:00FermiNRC Region 3Emergency Diesel Generator
Shutdown Cooling
Residual Heat Removal
At 2305 EDT on July 1, 2020, while in Mode 5 for Refueling Outage 20 with no core alterations in progress, Fermi 2 experienced a loss of Division 2 offsite power (345 kV) which resulted in a valid automatic initiation of the Division 2 Emergency Diesel Generators (EDG) 13 and 14. EDG 13 and 14 started as expected to supply their associated busses. Division 1 offsite power remains operable and powering the Division 1 Residual Heat Removal (RHR) system in Shutdown Cooling (SDC) mode of operation. Division 1 EDGs 11 and 12 remain operable and available. The cause of the loss of Division 2 offsite power is under review and has preliminarily been determined to be caused by Mayfly accumulation in and around the Division 2 (345 kV) switchyard. Actions have been put in place to minimize and deter Mayflies from gathering near plant switchyards. All systems responded as expected for the loss of Division 2 offsite power and no loss of SDC occurred. There was no impact to the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. The event is reportable pursuant to 10 CFR 50.72(b)(3)(iv)(A), as a valid specified system actuation.
ENS 5475322 June 2020 13:45:00Watts BarNRC Region 2

At 1304 EDT on June 22, 2020, Watts Bar Nuclear Plant (WBN) Units 1 and 2 initiated voluntary communication to the State of Tennessee and local officials as part of the Nuclear Energy Institute (NEI) Groundwater Protection Initiative (GPI), after receiving analysis results for one on-site monitoring well that indicated tritium activity above the GPI voluntary communication threshold. WBN identified and corrected the cause. This condition did not exceed any NRC regulations or reporting criteria. This notification is being made solely as a four-hour, non-emergency notification for a Notification of Other Government Agency. This event is reportable in accordance with 10 CFR 50.72(b)(2)(xi).

There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.

ENS 5475222 June 2020 01:00:00CatawbaNRC Region 2HVACAt 2100 on June 21, 2020, a condition was discovered which will require corrective maintenance activities to be performed on the Technical Support Center (TSC) HVAC. The work will include repair of the Condensing Unit system. The estimated duration of repair is unknown at this time. If an emergency is declared requiring TSC activation during this period, the TSC will be staffed and activated using existing emergency planning procedures unless the TSC becomes uninhabitable. If relocation of the TSC becomes necessary, the Emergency Director will relocate the TSC staff to the alternate facility. This is an eight-hour, non-emergency notification for a loss of Emergency Assessment Capability. This event is reportable in accordance with 10 CFR 50.72(b)(3)(xiii) because the discovered condition of the TSC affects the functionality of an emergency response facility. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
ENS 5474918 June 2020 20:37:00Beaver ValleyNRC Region 1On June 18, 2020, Beaver Valley Power Station, Unit 1 determined that leakage from an outside out-of-service liquid waste pipe that is within a radiologically controlled area contains several isotopes. Analysis indicates greater than 2,000 picoCuries per liter of tritium, and isotopes of Mn-54, Co-58, Co-60, and Cs-137 are above the lower limit of detection. At 1725 EDT, in accordance with site procedures and NEI 07-07, 'Industry Ground Water Protection Initiative,' notification to the Commonwealth of Pennsylvania was planned. At 1930 EDT notification to the Commonwealth of Pennsylvania was completed. The leak is currently contained. The leakage did not exceed any NRC regulations or reporting criteria. This notification is being made solely as a four-hour, non-emergency notification for a planned notification of other government agency. This event is reportable in accordance with 10 CFR 50.72(b)(2)(xi). There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
ENS 547428 June 2020 18:52:00SummerNRC Region 2

At 1725 EDT on 6/8/2020, V.C. Summer Nuclear Station reported a transmission fluid spill to the South Carolina Department of Health and Environmental Control. The spill was the result of a hydraulic hose leak during equipment testing. This spill did not violate any NRC regulations or reporting criteria. This notification is being made solely as a four-hour, non-emergency notification for a Notification of Other Government Agency. This event is reportable in accordance with 10 CFR 50.72(b)(2)(xi).

There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.

The spill resulted in 1 - 2 ounces of transmission fluid being released into the Monticello Reservoir.

ENS 547418 June 2020 01:08:00Grand GulfNRC Region 4On June 7, 2020, at 2238 CDT Grand Gulf Nuclear Station (GGNS) was notified by Claiborne County that one Emergency Notification Siren located on US Hwy 61 South had actuated. Claiborne County was informed that no emergency exists at GGNS. The alarming siren has since been secured. Notification is being provided to the NRC in regards to the potential for media inquiry. The licensee informed the NRC Resident Inspector.
ENS 547406 June 2020 12:25:00SeabrookNRC Region 1Steam Generator
Feedwater
Main Condenser
Manual Scram

At 0920 (EDT), with the unit in Mode 1 and 100 percent power, the reactor was manually tripped due to group 1 of control rod bank 'B' fully inserting into the core. All systems responded normally post trip. Operations has stabilized the plant in mode 3 at NOP/NOT (normal operating pressure and temperature). Decay heat removal is being accomplished via the steam dumps in the steam pressure mode to the main condenser.

Emergency feedwater actuated due to low low steam generator level as expected.

This event is being reported pursuant to 10CFR50.72(b)(2)(iv)(B) and 10CFR50.72(b)(3)(iv)(A)

The senior NRC Resident Inspector has been notified. The plant response to the trip was uncomplicated. All safe shutdown equipment is available. There were no reliefs or safeties actuated during the transient. The licensee manually tripped eight days ago for the same condition. See EN #54731.

ENS 547385 June 2020 10:39:00MillstoneNRC Region 1Control Room Emergency Ventilation

EN Revision Text: CONTROL ROOM BOUNDARY DOOR FAILURE On June 5, 2020, at 0320 (EDT) a loss of control room envelope (CRE) was declared inoperable due to failure of door 204-36-007. The door was repaired at 0322 (EDT), restoring the CRE to operable. The NRC Resident Inspector, state, and local authorities were notified.

  • * * RETRACTION ON 07/09/2020 AT 1443 EDT FROM GERALD A. BAKER TO OSSY FONT * * *

The purpose of this call is to retract a report made on June 5, 2020, NRC Event Number EN54738. NRC Event Report number EN54738 describes a condition at Millstone Power Station Unit 2 (MPS2) in which a control room envelope boundary door was discovered to not be able to fully close due to the latching mechanism being stuck in the extended position. The condition was reported to the NRC pursuant to 10 CFR 50.72(b)(3)(v)(D) via an 8 hour prompt report as an event or condition that at the time of discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident. Upon further review, MPS2 determined that there was no loss of safety function. An engineering evaluation determined that even with the control room boundary door unable to be fully closed due to the latching mechanism being stuck in, the extended position, control room air in-leakage would not have been sufficient to prevent the control room emergency ventilation system from performing its safety function. Therefore, this condition is not reportable and NRC Event Number EN54738 is being retracted. The basis for this conclusion has been provided to the NRC Resident Inspector. Notified R1DO (Dimitriadis).

  • * * UPDATE FROM MICHAEL GAGNON TO BRIAN P. SMITH AT 1444 EDT ON 10/01/2020 * * *

The purpose of this call is to provide an update to the retraction for a report made on June 5, 2020, NRC Event Number EN54738. The retraction being updated was made on 7/9/2020 at 1443 hours. NRC Event Report number EN54738 describes a condition at Millstone Power Station Unit 2 (MPS2) in which a control room envelope boundary door was discovered to not be able to fully close due to the latching mechanism being stuck in the extended position. The condition was reported to the NRC pursuant to 10 CFR 50.72(b)(3)(v)(D) via an 8 hour prompt report as an event or condition that at the time of discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident (the Control Room Envelope). A subsequent engineering evaluation of the conditions that existed at the time, determined that the inability of the control room boundary door to fully close due to the latching mechanism being stuck in the extended position did not have an adverse impact upon the ability of the CRE to perform its safety function. The CRE remained operable throughout this event, and the ventilation system would have performed its safety function. Therefore, this condition is not reportable and NRC Event Number EN54738 is being retracted. The basis for this conclusion has been provided to the NRC Resident Inspector. Notified R1DO (Lally).

ENS 547353 June 2020 17:10:00McGuireNRC Region 2A non-licensed employee supervisor had a confirmed positive for drugs during a random fitness-for-duty test. The employee's access to the plant has been terminated.
ENS 547332 June 2020 19:41:00BrunswickNRC Region 2On June 2, 2020, at 1905 Eastern Daylight Time (EDT), Brunswick Steam Electric Plant (BSEP) made a report to the Department of Transportation (DOT) concerning the identification during receipt inspection of removable contamination in excess of 49 CFR 173.443(a) limits on an empty Type 'A' transportation shipping cask received at BSEP. All smears taken on the cask rain cover, trailer bed, and tires were less than minimum detectable activity for removable contamination. This notification is being made as a four-hour, non-emergency notification for a Notification of Other Government Agency. This event is reportable in accordance with 10 CFR 50.72(b)(2)(xi). There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
ENS 5473129 May 2020 16:41:00SeabrookNRC Region 1Steam Generator
Feedwater
Main Condenser
Manual ScramAt 1403 EDT, with the unit in Mode 1 and 100 percent power, the reactor was manually tripped due to Group 1 of Control Rod Bank 'B' unexpectedly inserting. All systems responded normally post-trip. Operations stabilized the plant in Mode 3 at 557 degrees Fahrenheit. Decay heat removal is being accomplished via the steam dumps in the steam pressure mode to the main condenser. Emergency feedwater actuated due to low low steam generator level as expected. This event is being reported pursuant to 10 CFR 50.72(b)(2)(iv)(B) and 10 CFR (b)(3)(iv)(A). The NRC Senior Resident Inspector has been notified.
ENS 5472927 May 2020 11:35:00CookNRC Region 3On 5/27/20 at approximately 0912 EDT, the Operations Shift Manager was made aware that the Berrien County Sheriff's Department (BCSD) inadvertently actuated the emergency sirens during a planned weekly test. BCSD notified Cook Nuclear Plant that an audible test was initiated instead of a silent test. All Emergency Notification sirens remain in service. No press release is planned by the licensee at this time. This notification is being made under 10 CFR 50.72(b)(2)(xi), Offsite Notification, as a four (4) hour report. The licensee has notified the NRC Resident Inspector.
ENS 5472726 May 2020 15:55:00SurryNRC Region 2A contract foreman had a confirmed positive for alcohol during a random fitness-for-duty test. The employee's access to the plant has been terminated. The licensee notified the NRC Resident Inspector.
ENS 5472626 May 2020 13:17:00FermiNRC Region 3A non-licensed employee supervisor had a confirmed positive for alcohol during a follow-up fitness-for-duty test. The employee's access to the plant has been terminated. The licensee notified the NRC Resident Inspector.
ENS 5472525 May 2020 08:44:00Grand GulfNRC Region 4Feedwater
Reactor Protection System
Emergency Diesel Generator
Main Steam Isolation Valve
Automatic ScramAn (automatic) reactor SCRAM occurred at 0433 CDT, on 05/25/2020, from 66 percent core thermal power. The cause of the SCRAM was due to a Main Turbine Trip. The cause of the Turbine Trip is under investigation. All systems responded as designed. No loss of offsite power or (Emergency Safety Feature) (ESF) power occurred. No (Emergency Core Cooling System) (ECCS) or Emergency Diesel Generator initiations occurred. Main Steam Isolation valves remained open and no radioactive release occurred due to this event. The plant is stable in mode 3. This event is being reported under 10 CFR 50.72(b)(2)(iv)(B), as any event or condition that results in actuation of the Reactor Protection System (RPS), when the reactor is critical. The NRC Resident Inspector has been notified." Decay heat removal is through the Feedwater and Condensate System.
ENS 5472421 May 2020 17:38:00WaterfordNRC Region 4A licensed operator had a confirmed positive for alcohol during a pre-access fitness-for-duty test. The individual's unescorted access has been terminated.
ENS 5472020 May 2020 12:07:00Watts BarNRC Region 2Emergency Diesel GeneratorAt 0521 EDT on May 20, 2020, with Unit 2 in Mode 3 at 0 percent power and Unit 1 defueled, an actuation of the Emergency Diesel Generator (EDG) System occurred while transferring the 1B-B 6.9kV Shutdown Board (SDBD) from the maintenance feed to its normal power supply. The reason for the 1B-B 6.9kV SDBD failing to transfer to the normal power supply is under investigation. The EDGs automatically started as designed when a valid actuation signal was received. The event is being reported in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the EDGs. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
ENS 5471819 May 2020 19:57:00Watts BarNRC Region 2At 1329 EDT on May 19, 2020, it was discovered that the main control room (MCR) envelope was inoperable due to a control room envelope (CRE) door being found ajar; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v). The CRE door was closed, restoring the MCR envelope to operable at 1331 EDT. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
ENS 5471615 May 2020 13:25:00SalemNRC Region 1At 0947 (EDT) on 5/15/20, Salem reported to the New Jersey Department of Environmental Protection a sheen on the Delaware River. This discovery did not violate any NRC (Nuclear Regulatory Commission) regulations or reporting criteria. This notification is being made solely as a four-hour, non-emergency notification for a Notification of Other Government Agency. This event is reportable in accordance with 10 CFR 50.72(b)(2)(xi). There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. The licensee will be notifying the National Response Center and Lower Alloways Creek Township. The substance spilled was less than one pint of hydraulic oil.
ENS 5471414 May 2020 19:28:00South TexasNRC Region 4At 1535 CDT, on 5/14/2020, it was determined that approximately 10 gallons of hydraulic oil was spilled during dredging activities into the STP Intake Basin (adjacent to the Colorado River). Cleanup using oil booms is underway and there is no longer a visible sheen. The cause of the hydraulic oil spill is under investigation. The Texas General Land Office was notified at 1610 CDT. The NRC Resident Inspector has been notified.
ENS 5471214 May 2020 18:36:00CatawbaNRC Region 2At approximately 1430 (EDT) on May 14, 2020, Catawba Nuclear Station (CNS) requested offsite transport for treatment of a contractor to an offsite medical facility. Upon arrival of the coroner, the individual was declared deceased at 1630 (EDT) on May 14, 2020. The fatality was not work-related and the individual was outside of the Radiological Controlled Area. No news release by CNS is planned. Notifications are planned to the South Carolina Division of Occupational Safety and Health. This is a four-hour notification, non-emergency for a notification of other government agency. This event is reportable in accordance with 10 CFR 50.72(b)(2)(xi). The NRC Resident Inspector has been notified.
ENS 5471013 May 2020 18:01:00ByronNRC Region 3At 1000 CDT on May 13, 2020, the Byron Station Technical Support Center (TSC) emergency ventilation system inlet isolation damper would not open as required to support system operation. This failure affected the ability of the TSC ventilation system to maintain adequate radiological habitability in the event of an emergency with an airborne radiological release. All other capabilities of the TSC were unaffected by this condition. If an emergency was declared requiring TSC activation during this period, the TSC would be staffed and activated using existing emergency planning procedures. If the TSC became uninhabitable, the Station Emergency Director would relocate the TSC staff to an alternate TSC location in accordance with applicable procedures. The TSC emergency ventilation system inlet isolation damper has been repaired and is now functional. This event is reportable in accordance with 10 CFR 50.72(b)(3)(xiii) because the discovered condition affected the functionality of an emergency response facility. The NRC Resident Inspector has been notified.
ENS 5470913 May 2020 13:10:00Browns FerryNRC Region 2Primary Containment Isolation System
Shutdown Cooling
Residual Heat Removal
Reactor Water Cleanup
This 60-day telephone notification is being made per the reporting requirements specified by 10 CFR 50.73(a)(2)(iv)(A) and 10 CFR 50.73(a)(1) to describe an invalid actuation of a general containment isolation signal affecting more than one system. On March 16, 2020, at approximately 0102 CDT, Browns Ferry Nuclear Plant (BFN), Unit 3 received motor trip-out alarms and diagnosed Group 2 and 3 Primary Containment Isolation System (PCIS) Isolations, 3C Residual Heat Removal (RHR) Pump tripping and Reactor Water Cleanup (RWCU) system isolating. All affected safety systems responded as expected. BFN, Unit 3, was nearing the end of the U3R19 refueling outage at the time of the event, and was still dependent on the Shutdown Cooling (SDC) system. Plant conditions which initiate PCIS Group 2 actuations are Reactor Vessel Low Water Level (Level 3) or High Drywell Pressure. The PCIS Group 3 actuations are initiated by Reactor Vessel Low Water Level (Level 3) or Reactor Water Cleanup Area High Temperature. At the time of the event, these conditions did not exist: therefore, the PCIS actuation was invalid. The event was determined to have been caused by clearance restoration activities in an unprotected control panel. A fuse re-installation inadvertently created a fault condition between two different plant 120 VAC power sources when the fuse holder's lower spring clip contacted a different fuse. This was a result of age-related degradation of the fuse holder, its close proximity to other fuses, and the lack of insulating isolation barriers between fuses. There were no safety consequences or impact to the health and safety of the public as a result of this event. This event was entered into the Corrective Action Program as Condition Report 1594925. The NRC Resident Inspector has been notified of this event.
ENS 5470813 May 2020 05:38:00SequoyahNRC Region 2Steam Generator
Main Steam Isolation Valve
Auxiliary Feedwater
Automatic ScramAt 0208 EDT on 05/13/2020, Sequoyah Unit 1 was at 100% power when an automatic reactor trip signal was received concurrent with a low steam line pressure safety injection signal. The low steam line pressure safety injection signal was actuated from the steam pressure rate of decrease feature. Main steam isolation valves (MSIVs) automatically closed as designed and steam generator pressures stabilized following the isolation. All other safety-related equipment operated as designed, with the exception of 1-FCV-61-122 Glycol inboard containment isolation valve which failed to automatically isolate on a Phase A containment isolation signal. The corresponding outboard containment isolation valve, 1-FCV-61-110, automatically isolated as designed which isolated penetration X-114. Safety injection was terminated at 0221 EDT 5/13/20, and Unit 1 is currently being maintained in Mode 3 at normal operating temperature and pressure with auxiliary feedwater supplying the steam generators and decay heat removal via steam generator atmospheric relief valves. There is no indication of any primary to secondary leakage. The electrical alignment is normal with shutdown power supplied from off-site power. There is no current operational impact to Unit 2. There is no impact on public health or safety. Post safety injection actuation investigation is in progress. The NRC Resident Inspector has been notified.
ENS 5470713 May 2020 01:14:00CatawbaNRC Region 2Reactor Coolant System

During the performance of reactor vessel closure head (RVCH) inspections, at 2220 EDT on May 12, 2020, it was determined that the Unit 1 RVCH penetration nozzle number 18 did not meet ASME code case N-729-4 requirements. A surface examination (penetrant test) identified a linear indication on nozzle number 18. The indication was not through-wall as determined by ultrasonic testing. The condition of the Unit 1 reactor vessel head penetration nozzle number 18 will be resolved prior to re-installation of the Unit 1 reactor vessel head. This event is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(ii)(A).

There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.

ENS 5470111 May 2020 13:07:00Palo VerdeNRC Region 4Service water
Spray Pond
The following event descriptions are based on information currently available. If through subsequent reviews of these events additional information is identified that is pertinent to the events or alters the information being provided at this time a follow-up notification will be made via the ENS or under the reporting requirements of 10 CFR 50.73. This telephone notification is being made pursuant to the reporting requirements of 10 CFR 50.73(a)(2)(iv)(A) and 50.73(a)(1) to describe invalid actuations of both trains of the Palo Verde Nuclear Generating Station (PVNGS) Unit 3 essential spray pond (SP) system, which serves as an emergency service water system that does not normally run and serves as an ultimate heat sink as described in 10 CFR 50.73(a)(2)(iv)(B)(9). This notification covers two similar, but separate invalid actuations occurring in Unit 3 on March 14, 2020 at 12:44 (MST) and again on April 25, 2020 at 12:10 (MST). On each day, an invalid actuation of the Unit 3 train "B" Fuel Building Essential Ventilation Actuation Signal (FBEVAS) occurred during performance of the Balance of Plant Engineered Safety Features Actuation System weekly auto test. The auto/manual pushbutton was depressed to initiate the test and the sequencer immediately tripped FBEVAS train "B" with subsequent cross trip of FBEVAS train "A". These actuations resulted in complete and successful actuations of both trains of essential spray pond pumps. The events were entered into the PVNGS corrective action program and a station evaluation is in progress. There was no adverse impact to public health and safety nor to plant employees. The NRC resident inspectors have been informed.
ENS 546976 May 2020 14:11:00Browns FerryNRC Region 2Reactor Protection System
Primary Containment Isolation System
Reactor Building Ventilation
Reactor Water Cleanup
Control Room Emergency Ventilation
This 60-day telephone notification is being made per the reporting requirements specified by 10 CFR 50.73(a)(2)(iv)(A) and 10 CFR 50.73(a)(1) to describe an invalid actuation of a general containment isolation signal affecting more than one system. On March 8, 2020, at approximately 2021 CDT, Browns Ferry Nuclear Plant Unit 2 experienced an unexpected loss of the 2A Reactor Protection System (RPS). This resulted in Primary Containment Isolation System (PCIS) groups 2, 3, 6, and 8 isolations, and the initiation of Standby Gas Treatment Trains A and B, and Control Room Emergency Ventilation System Train A. All affected safety systems responded as expected. Plant conditions which initiate PCIS Group 2 actuations are Reactor Vessel Low Water Level (Level 3) or High Drywell Pressure. The PCIS Group 3 actuations are initiated by Reactor Vessel Low Water Level (Level 3) or Reactor Water Cleanup Area High Temperature. The PCIS Group 6 actuations are initiated by Reactor Vessel Low Water Level (Level 3), High Drywell Pressure, or Reactor Building Ventilation Exhaust High Radiation (Reactor Zone or Refuel Zone). The PCIS Group 8 actuations are initiated by Low Reactor Vessel Water Level (Level 3) or High Drywell Pressure. At the time of the event, these conditions did not exist; therefore, the actuation of the PCIS was invalid. The RPS MG Set trip was believed to have been caused by an intermittent short across a spike suppressor, which led to a loss of generator output signal to a voltage regulator. The affected components have been replaced. There were no safety consequences or impact to the health and safety of the public as a result of this event. This event was entered into the Corrective Action Program as Condition Report 1593265. The NRC Resident Inspector has been notified of this event.
ENS 546934 May 2020 23:40:00LaSalleNRC Region 3High Pressure Core Spray

EN Revision Text: DIESEL GENERATOR COOLING WATER SYSTEM DECLARED INOPERABLE This report is being made pursuant to 10 CFR 50.72(b)(3)(v)(D), Event or Condition that could have prevented fulfillment of a Safety Function needed to mitigate the Consequences of an Accident. A through wall leak was found on piping connected to the Division 3 Diesel Generator (DG) Cooling Water Strainer. This condition has been evaluated and the Division 3 DG Cooling Water System has been declared inoperable. The Division 3 DG Cooling Water System is a support system for the Division 3 Emergency DG and the High Pressure Core Spray System (HPCS). The NRC Resident Inspector has been notified.

  • * * RETRACTION ON MAY 8, 2020 AT 1709 EDT FROM JOE MESSINA TO BRIAN LIN * * *

This update retracts Event Notification #54693, which reported a condition that could have potentially prevented fulfillment of a safety function needed to mitigate the consequences of an accident. An evaluation of the flaw on the piping connected to the Unit 2 Division 3 Diesel Generator (DG) Cooling Water strainer concluded that the system would have remained operable. The High Pressure Core Spray system, supported by the operable DG Cooling Water system, remained operable and capable of performing its safety function. The NRC Resident Inspector has been notified. Notified R3DO (Stone).

ENS 546923 May 2020 22:28:00Nine Mile PointNRC Region 1On 5/3/2020 at 1100 EDT, Operations identified a step change in the Main Control Room ambient noise. The cause of the noise was a rise in vibrations on the Number 11 fan motor of the Main Control Room Ventilation Circulating Fan. Another step change in noise occurred and Operations swapped from the Number 11 fan motor to its redundant Number 12 fan motor, but the noise and vibrations did not improve. The two independent motors are connected to the blower shaft with belts on either end of the shaft. This entire fan and motor assembly is contained within the Main Control Room ventilation ducting and is not visible. At 1118 EDT, Operations shut off the Main Control Room Ventilation Circulating Fan due to Number 11 fan motor vibrations, declared the Main Control Room Air Treatment System inoperable, and entered the Technical Specification 3.4.5.e, 7-day action statement. At 1750 EDT, Maintenance entered the ductwork and informed Operations that the Number 11 fan bearing had catastrophically failed and because of the extent of damage and close physical proximity to the Number 12 fan motor, jeopardized its continued operation. As a result, Operations also declared the Number 12 fan motor inoperable and determined the event was reportable as a loss of safety function per 10 CFR 50.72(b)(3)(v)(D). The licensee notified the NRC Resident Inspector.
ENS 546913 May 2020 11:43:00SusquehannaNRC Region 1Reactor Protection System
Reactor Core Isolation Cooling
Main Turbine
Reactor Recirculation Pump
Automatic ScramAt 0821 EDT on May 3, 2020, the Susquehanna Steam Electric Station Unit 1 reactor automatically scrammed due to a trip of the Main Turbine. The Unit 1 reactor was operating at 76 percent reactor power following a ramp schedule to full power subsequent to a maintenance outage. The Control Room received indication of a Main Turbine trip with both divisions of the Reactor Protection System actuated and all control rods inserted. The Reactor Recirculation Pumps tripped on End of Cycle - Recirculation Pump Trip. Reactor water level lowered to -1 inch causing Level 3 (+13 inches) isolations. No Emergency Core Cooling System or Reactor Core Isolation Cooling actuations occurred. The operations crew subsequently maintained reactor water level at the normal operating band using Reactor Feed Water. No Steam Relief Valves opened. The reactor is currently stable in Mode 3. Investigation into the trip of the Main Turbine is in progress. The NRC Resident Inspector was notified. A voluntary notification to the Pennsylvania Emergency Management Agency and press release will occur. This event requires a 4-hour Emergency Notification System (ENS) notification in accordance with 10 CFR 50.72(b)(2)(iv)(B) and an 8-hour ENS notification in accordance with 10 CFR 50.72(b)(3)(iv)(A) and 10 CFR 50.72(b)(3)(iv)(B).