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 Entered dateSiteRegionReactor typeSystemScramEvent description
ENS 5462127 March 2020 15:18:00Palo VerdeNRC Region 4Shutdown Cooling
Steam Bypass Control System
The following is a summary of information obtained from Palo Verde via email: During pre-installation testing, five Masoneilan Model transducers were identified as unable to be calibrated prior to installation. These transducers were received by the vendor as safety-related components and are used to provide remote control operation of the Atmospheric Dump Valves (ADVs). The ADVs provide a safety grade method for cooling the unit to Shutdown Cooling System entry conditions, should Palo Verde's preferred heat sink via the Steam Bypass Control System to the condenser and/or atmosphere not be available. The transducer receives a 4-20 mA signal and translates it to a 3-15 psi output to the ADV positioner. This is accomplished by varying the supply air from 23-30 psi down to the appropriate 3-15 psi signal. Palo Verde provided an Interim 10 CFR 21 Report for the five Masoneilan Model 8005N transducers, Part 21 log number 2019-36-00, ML 19323C971, which was submitted by Arizona Public Service (APS) Company on November 15, 2019. An evaluation of the transducers was completed on March 19, 2020. The evaluation concluded that the inability of the transducers to be calibrated represented a defect. The licensees affected are undetermined at this time. Palo Verde has been in communication with the vendor. The vendor has currently not provided an extent of condition. Point of Contact: Lorraine Weaver (602) 448-5915
ENS 5461426 March 2020 10:45:00McGuireNRC Region 2

EN Revision Text: DEGRADED CONDITION On March 26, 2020, while McGuire Unit 2 was shut down for a scheduled refueling outage, the reactor vessel head penetrations were being examined in accordance with the in-service Inspection Program. Ultrasonic examinations identified a relevant indication in the Control Rod Drive Mechanism nozzle number 35 that did not meet the acceptance criteria under ASME, Section XI IWB-3600, 'Analytic Evaluation of Flaws.' Actions to address the relevant indication will be taken in accordance with the applicable codes, standards, and regulations. This event is being reported as an eight-hour non-emergency notification per 10 CFR 50.72(b)(3)(ii)(A). The relevant indication has no impact on the health and safety of the public or station employees. The NRC Resident Inspector has been notified.

  • * * RETRACTION ON 3/29/2020 AT 1700 EDT FROM TOM BERNARD TO BRIAN P. SMITH * * *

McGuire is retracting the eight hour non-emergency notification made on March 26, 2020, at 10:45 ET (EN#54614). A subsequent evaluation determined that the suspect indication identified during ultrasonic examination of Control Rod Drive Mechanism nozzle number 35 is not service induced nor representative of primary water stress corrosion cracking (PWSCC). The indication has been classified as "non-relevant" and is not reportable as a degraded condition. The senior NRC Resident Inspection has been notified. Notified R2DO (Miller).

ENS 5461125 March 2020 15:28:00Davis BesseNRC Region 3Reactor Protection System
Main Condenser
Manual ScramAt 1240 (EDT) on March 25, 2020, with the Unit in Mode 2 at approximately 0% (zero percent) power starting up from a refueling outage, the reactor was manually tripped due to a trip of two of four Reactor Coolant Pumps. The trip was not complex, with all systems responding normally post-trip. Operations responded and stabilized the plant. Decay heat is being removed by discharging steam to the main condenser. The cause of the Reactor Coolant Pump trips is under investigation. Due to the Reactor Protection System actuation while critical, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B). There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
ENS 5460725 March 2020 03:30:00SalemNRC Region 1Steam Generator
Reactor Protection System
Auxiliary Feedwater
Manual ScramAt 0056 EDTon March 25, 2020, with Unit 1 at 17 percent power during a unit power ascension, the reactor was manually tripped due to the failure of the 11 Rod Control Motor Generator caused by a malfunction of its associated Voltage Regulator. The trip was not complex, with all systems responding normally post-trip. An actuation of the Auxiliary Feedwater system occurred following the manual reactor trip as expected due to low level in the steam generators. The unit is stable in Mode 3. Decay heat is being removed by the Atmospheric Steam Dumps and Auxiliary Feedwater System. Salem Unit 2 was not affected. Due to the actuation of the Reactor Protection System actuation while critical, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B), This event is also being reported as an eight hour non-emergency notification in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the Auxiliary Feedwater System. There was no impact to the health and safety of the public or plant personnel. The NRC Resident lnspector has been notified.
ENS 5460524 March 2020 17:15:00South TexasNRC Region 4Emergency Diesel Generator
Auxiliary Feedwater
At 1046 CDT on 3/24/2020, with Unit 1 defueled and Unit 2 in Mode 1 at 100 percent power, the South Texas Project (STP) South switchyard electrical bus was deenergized. This resulted in a loss of power to Standby Transformer 2 which was supplying power to the Engineered Safety Features (ESF) 4160v busses for Unit 1 A- and C-Trains, and Unit 2 B-Train. Emergency Diesel Generators (EDGs) 11, 13, and 22 automatically started in response to the undervoltage condition. The cause for the loss of the South switchyard electrical bus was an error in relay testing in the switchyard. This event is reportable under 10 CFR 50.72(b)(3)(iv)(A) as an event that resulted in the valid actuation of emergency AC electrical power systems (50.72(b)(3)(iv)(B)(8)) as well as the Unit 1 A- and C-Train and Unit 2 B-Train Reactor Containment Fan Coolers (50.72(b)(3)(iv)(B)(7)) and Unit 2 B-Train Auxiliary Feedwater pump (50.72(b)(3)(iv)(B)(6)). There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
ENS 5460324 March 2020 16:02:00BrunswickNRC Region 2Reactor Coolant System
Primary Containment Isolation System
Shutdown Cooling
Manual ScramAt 1205 Eastern Daylight Time (EDT) on March 24, 2020, a Technical Specification-required shutdown was initiated on Unit 1 due to indication of a leak in the drywell. Technical Specification Action 3.4.4.A, Unidentified Reactor Coolant System (RCS) leakage increase not within limit, requires RCS leakage to be reduced to within limits within 8 hours. It was expected that the leakage would not have been reduced to within limits within the required Technical Specification completion time; therefore, this event is being reported in accordance with 10 CFR 50.72(b)(2)(i). Reactor water level reached low level 1 (LL1) following the reactor shutdown. The LL1 signal causes Group 2 (i.e., floor and equipment drain isolation valves), Group 6 (i.e., monitoring and sampling 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. Due to the valid Primary Containment Isolation System (PCIS) actuation, this event is also being reported in accordance with 10 CFR 50.72(b)(3)(iv)(A). Unit 2 is not affected by this event. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
ENS 5459923 March 2020 13:36:00HarrisNRC Region 2Steam Generator
Feedwater
Reactor Protection System
Auxiliary Feedwater
Automatic ScramOn March 23, 2020, at 1013 EDT, with Harris Nuclear Plant Unit 1 in Mode 1, at 100 percent power, an unplanned actuation of the reactor protection system occurred. This resulted in an automatic reactor trip. The trip occurred during the restoration of the auto-stop turbine trip function during a planned maintenance evolution. All safety systems functioned as expected. Auxiliary Feedwater started as designed and was secured. Steam generator levels are being maintained by normal feedwater through the feedwater regulator bypass valves. Decay heat is being removed by using the condenser steam dump flow path. Due to the unplanned Reactor Protection System actuation while critical and the expected Auxiliary Feedwater actuation, this event is being reported as a four hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B) and an eight hour, non-emergency notification per 10 CFR 50.72(b)(3)(iv)(A). There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
ENS 5459621 March 2020 23:46:00VogtleNRC Region 2Emergency Diesel GeneratorAt 1644 EDT with Unit 1 in Mode 6 at 0 percent power, an actuation of the Unit 1 Bravo Train Emergency Diesel Generator system (EDG) occurred during Engineered Safety Feature Actuation System (ESFAS) testing. The reason for the EDG auto-start signal was a loss of voltage on the Bravo train safety related electrical bus due to the EDG output breaker opening. The EDG was already running at the time of the loss of voltage on the bus. This 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 EDG system. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. There was no impact to Unit 2.
ENS 5459420 March 2020 17:47:00Quad CitiesNRC Region 3Emergency Diesel Generator
Residual Heat Removal
On March 20, 2020, at 1025 hours (CDT), Unit 2 MCC (motor control center) 28/29-5 failed to transfer to its alternate feed during surveillance testing. This would result in MCC 28/29-5 being de-energized in the event of a DBA LOCA (design basis accident loss of coolant accident) in which the Unit 1 Emergency Diesel Generator fails to energize Bus 29. Consequently, the LPCI (low pressure coolant injection) Injection Valve (MO 2-1001-29A/B) would not have power to open on the loop selected by LPCI Loop Select. This renders both divisions of the LPCI mode of Residual Heat Removal system inoperable. Technical Specification 3.5.1, Condition E had previously been entered during testing, requiring restoration of LPCI in 72 hours. No other ECCS (emergency core cooling) systems were inoperable at the time of the event. Troubleshooting and repairs are in progress. This event is reportable under 10 CFR 50.72(b)(3)(v)(D) as an event or condition that could have prevented fulfillment of a safety function. The plant is still in its 72-hr. LCO action statement. The licensee has notified the NRC Resident Inspector and the state of Illinois Emergency Management Agency.
ENS 5458717 March 2020 19:38:00South TexasNRC Region 4

At 1532 CDT, on 3/17/2020, it was reported to the Unit 1 Control Room that less than one gallon of hydraulic oil was spilled into the Colorado River during dredging activities. Cleanup using oil booms was completed at 1747 CDT. The cause of the hydraulic oil spill is under investigation.

The Texas General Land Office was notified at 1558 CDT.

The NRC Resident Inspector has been notified.

ENS 545706 March 2020 14:19:00Palo VerdeNRC Region 4A non-licensed contract supervisor had a confirmed positive for a controlled substance during an initial Fitness For Duty screening test. The individuals plant access has been terminated. The NRC Resident Inspector has been notified.
ENS 545695 March 2020 21:14:00SeabrookNRC Region 1

On March 05, 2020, at 2100 EST, the site commenced a planned upgrade of the main plant computer system (MPCS). During this upgrade, the normal computer data will not be available to the emergency response facilities, but compensatory capabilities will be in place. The scheduled duration for the MPCS upgrade is 96 hours. Since the compensatory measures will be in place in excess of 72 hours, this condition is being reported pursuant to 10 CFR 50.72(b)(3)(xiii).

The NRC Resident Inspector has been notified.

ENS 545675 March 2020 16:48:00FermiNRC Region 3Secondary containmentOn March 05, 2020, at 1235 EST, with the reactor at 100 percent core thermal power and steady state conditions, plant personnel notified the main control room that both doors in the secondary containment airlock on the reactor building fifth floor were opened simultaneously for a period of approximately three seconds (i.e., from 12:35:00 to 12:35:03 EST). The failure of this interlock, which is intended to prevent both doors from being opened simultaneously, resulted in the Technical Specification (TS) Surveillance Requirement (SR) 3 .6.4.1.3 not being met. The maximum secondary containment pressure observed during that time remained within TS limits. There were no radiological releases associated with this event. Declaring secondary containment inoperable as a result of not meeting TS SR 3.6.4.1.3 is reportable under 10 CFR 50.72(b)(3)(v)(C) as an event or condition that could have prevented the fulfillment of a safety function needed to control the release of radioactive material. The licensee has notified the NRC Resident Inspector.
ENS 545624 March 2020 15:35:00Nine Mile PointNRC Region 1Manual Scram

At 1205 EST, on March 4, 2020, Nine Mile Point Unit 2 initiated a manual reactor scram due to lowering Electrohydraulic Control System (EHC) level in the turbine control system. The cause of the lowering level was a leak in the EHC system piping.

"All control rods inserted. There were no safety system actuations. The cause of the EHC leak is being investigated.

The NRC Resident has been notified. Additionally, the licensee notified the New York State Public Service Commission.

ENS 545614 March 2020 12:24:00South TexasNRC Region 4

EN Revision Text: NOTIFICATION TO OTHER GOVERNMENT AGENCY On March 4, 2020, an actual Unusual Event code was inadvertently sent to an offsite agency, Institute of Nuclear Power Operations (INPO), and to a former NRC Resident Inspector during a planned emergency response drill. The NRC Resident Inspector has been notified.

  • * * RETRACTION ON 3/5/2020 AT 1554 EST FROM RONALD ROHAN TO DONALD NORWOOD * * *

Based on further review of the NRC reporting guidance relative to these criteria, STP has concluded that this condition is below the reporting threshold outlined in NUREG-1022 Revision 3. NUREG-1022 states the following (page 54): 'Licensees generally do not have to report media and government interactions unless they are related to the radiological health and safety of the public or on-site personnel, or protection of the environment. The condition originally reported in EN 54561 is not a news release or government notification and has no impact on the radiological health and safety of the public or on-site personnel, or protection of the environment. Therefore, STP is retracting EN 54561. The NRC Resident Inspector was notified on 3/5/2020 at 1310 CST. Notified R4DO Rick Deese.

ENS 545604 March 2020 02:07:00Palo VerdeNRC Region 4Steam Generator
Feedwater
Reactor Protection System
Emergency Diesel Generator
Auxiliary Feedwater

EN Revision Text: REACTOR TRIP DUE TO LOW STEAM GENERATOR LEVEL At 2050 MST on March 3, 2020, Unit 2 reactor automatically tripped on Low Steam Generator (SG) Number 1 level signal from the Reactor Protection System. The low SG level occurred as the result of a trip of both Main Feedwater Pumps, which tripped during restoration of power to the Main Feedwater Pump Lube oil control panel. Auxiliary Feedwater (AFAS-1 and AFAS-2) actuated due to low SG levels in both SG post reactor trip as designed. This event is being reported as a reactor protection system and a specified system actuation in accordance with the reporting criteria of 10 CFR 50.72(b)(2)(iv)(B) and 10 CFR 50.72(b)(3)(iv)(A). Following the reactor trip, all (control element assemblies) CEAs inserted fully into the core. All systems operated as expected. No emergency plan classification was required per the Emergency Plan. Safety related busses remained powered during the event from offsite power and the offsite power grid is stable. Unit 2 is stable and in Mode 3. Steam Generators are being fed via the class 1E powered motor driven auxiliary feedwater pump. The NRC Senior Resident Inspector has been informed. Units 1 and 3 were unaffected by the trip and remain at 100 percent power.

  • * * UPDATE FROM ALLAN BRIEFE TO DONALD NORWOOD AT 1231 EDT ON 5/4/2020 * * *

The event reported on March 4, 2020 (EN 54560) also included actuations of the Emergency Diesel Generators in response to the AFAS-1 and AFAS-2 actuations. The Class 4.16kV buses remained energized from off-site power. The NRC Senior Resident Inspector has been informed. Notified R4DO (Drake).

ENS 545562 March 2020 20:45:00South TexasNRC Region 4A non-licensed contract employee supervisor had a confirmed positive for illegal drugs 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 5453320 February 2020 15:04:00FitzPatrickNRC Region 1(On February 20, 2020, at 1240 EST, the Licensee determined the following information:) This notification is in reference to reports EN 54130 and LER 2019-002, which were retracted. James A. FitzPatrick Nuclear Power Plant received additional information on the technical basis for the retraction. Further review, including testing of the terminal blocks, demonstrated that the short circuit current would result in heat levels in excess of cable insulation ratings. Unprotected DC control circuits for non-safety related DC motors are routed between separate fire areas. A postulated fire in one area can cause a short circuit and potentially result in secondary fires or cable fires in other fire areas where the cables are routed. The secondary fires or cable failures degrade the degree of separation for redundant safe shutdown trains and are outside the assumptions of the 10 CFR 50 Appendix R Safe Shutdown Analysis. This condition is reportable in accordance with 10 CFR 50.72(b)(3)(ii)(B). Compensatory actions per the Technical Requirements Manual (TRM) for affected fire areas have been implemented. A modification to install fuses in the control circuits for 94P-2(M), 31P-7A(M), 31P-7B(M), and 94P-13(M) has been scheduled and shall correct this condition. The NRC Resident Inspector has been notified.
ENS 5453119 February 2020 10:20:00Watts BarNRC Region 2

EN Revision Text: NOTIFICATION OF UNUSUAL EVENT DUE TO FIRE IN CONTROL BUILDING At 0957 EST on February 19, 2020, a Notification of Unusual Event (NOUE) has been determined to be present at the Watts Bar plant Unit 1 under criteria HU4 for a fire potentially degrading the safety of the plant (fire for more than 15 minutes). The NRC Senior Resident Inspector has been notified for this event. Notified DHS SWO, FEMA Operations Center, CISA IOCC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email).

  • * * UPDATE ON 02/19/2020 AT 1151 EST FROM ANDREW WALDMANN TO DONALD NORWOOD * * *

The fire was declared extinguished at 1033 EST. The NOUE was terminated at 1126 EST. The investigation into the cause of the fire is in progress. Notified R2DO (Musser), NRR EO (Miller), and IRD MOC (Kennedy). Additionally, notified DHS SWO, FEMA Operations Center, CISA IOCC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email).

  • * * RETRACTION ON 2/20/2020 AT 1453 EST FROM MICHAEL BUTHEY TO RICHARD L. SMITH * * *

Watts Bar Nuclear Plant (WBN) is retracting Event Notice 54531 (NOUE notification) based on the following additional information. WBN reported a condition that was determined to meet the definition of a FIRE in the plant Emergency Preparedness Implementing Procedures (EPIP) based on indications available to the decision-maker at the time the declaration was made. A fire, without observation of flame, is considered present if large quantities of smoke and heat are observed. Moderate quantities of smoke were observed coming from an electrical cabinet not required to support safe plant operation. Once Fire Brigade personnel were able to access the affected room, no evidence of flame or significant heat was observed. Plant personnel ultimately determined that an overheated electrical component (transformer) resulted in the smoke. As such, the actual conditions did not meet the EPIP definition of a fire. The NRC Resident Inspector has been notified of this retraction. Notified R2DO (Musser), NRR EO (Miller), and IRD MOC (Kennedy).

ENS 5453219 February 2020 10:20:00Watts BarNRC Region 2Steam Generator
Reactor Protection System
Auxiliary Feedwater
Manual ScramAt 0936 EST on February 19, 2020, the Watts Bar Unit 1 reactor was manually tripped while operating at 100 percent power in response to loss of control of water level for steam generator number 3. All control and shutdown bank rods inserted properly in response to the manual reactor trip. All safety systems including Auxiliary Feedwater actuated as designed. The plant is stable with decay heat removal through Auxiliary Feedwater and Steam Dump Systems. There is no impact to Unit 2. The manual actuation of the Reactor Protection System (RPS) is being reported as a four-hour report under 10 CFR 50. 72(b)(2)(iv)(B). The expected actuation of the Auxiliary Feedwater System (an engineered safety feature) is being reported as an eight-hour report under 10 CFR 50.72 (b)(3)(iv)(A). The NRC Senior Resident Inspector has been notified for this event.
ENS 5453018 February 2020 20:20:00South TexasNRC Region 4

On February 18, 2020 a non-licensed contractor supervisor violated the station's FFD policy. The employee's unescorted access to South Texas has been terminated.

The NRC Resident Inspector has been notified.

ENS 5452917 February 2020 19:23:00South TexasNRC Region 4

At 1647 CST on 2/17/2020, it was determined that approximately two quarts of hydraulic oil were spilled into the Colorado River during preparation for dredging activities. Cleanup using an oil dispersant and oil booms is underway. The cause of the hydraulic oil spill is under investigation.

The Texas General Land Office was notified at 1717 CST. Additional reports were made to the Texas Commission of Environmental Quality, the Environmental Protection Agency National Response Center, and the Matagorda County Local Emergency Planning Committee.

The NRC Resident Inspector has been notified.

ENS 5452817 February 2020 14:51:00Duane ArnoldNRC Region 3At 0850 CST, on 2/17/2020, the Control Room was notified of a personnel medical event. The individual was transported to a local hospital via ambulance. At the time of transport, the individual was considered to be potentially contaminated because complete surveys could not be performed prior to transfer. Upon arrival at the hospital, the individual and clothing were surveyed by an accompanying Site Radiation Protection Technician and no contamination was found. This report is being made pursuant to 10 CFR 50.72(b)(3)(xii). The NRC Resident Inspector has been notified. The individual was not performing any work related activities at the time of event.
ENS 5452312 February 2020 21:51:00CatawbaNRC Region 2Reactor Protection System
Auxiliary Feedwater
Main Condenser
Automatic ScramAt 1800 EST, on February 12, 2020, with Unit 1 in Mode 1 at 100 percent power, the reactor automatically tripped due to a turbine trip. The trip was not complex, with all systems responding normally post trip. Because of the reactor trip, the Auxiliary Feedwater (AFW) System actuated as expected due to on ATWS Mitigation System Actuation Circuitry (AMSAC) signal. The AFW pumps started as designed when the valid system actuation was received. Operations responded and stabilized the plant. Decay heat is being removed by discharging steam to the main condenser using the condenser steam dump valves. Due to the Reactor Protection System (RPS) actuation while critical, this event is being reported as an 4-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B). This event is also being reported as an 8-hour non-emergency notification per 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the AFW system. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. The site remains in a normal electrical lineup. The cause of the turbine trip is under investigation.
ENS 5451711 February 2020 14:45:00South TexasNRC Region 4

On February 11, 2020, a licensed Senior Reactor Operator violated the station's fitness-for-duty policy. The employee's access to South Texas has been terminated.

The NRC Resident Inspector has been notified. The employee tested positive on a follow-up test for alcohol.

ENS 545093 February 2020 09:16:00OconeeNRC Region 2HVAC

At 0915 EST on February 3, 2020, planned upgrades to the Technical Support Center (TSC) and Operations Support Center (OSC) will begin. The work includes upgrades to furniture, carpet, telecommunications, celling tiles, and HVAC vent covers and the installation of new Audio-Visual equipment to include monitors, speakers, and microphones. The work duration is approximately eight weeks. If an emergency is declared requiring TSC and OSC activation during this period, the TSC and OSC will be staffed and activated at the alternate location in accordance with applicable site procedures. The Emergency Response Organization team has been notified of the TSC and OSC planned upgrades and the need to assemble and staff the alternate location during an emergency.

This is an eight-hour, non-emergency notification for a planned 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. There is no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.

ENS 545081 February 2020 23:06:00Wolf CreekNRC Region 4At 1845 CST on 2/1/2020, during surveillance testing (STS PE-015, Containment Purge Valve Leakage Test) containment leakage in excess of Technical Specification requirements was observed. A Technical Specification required shutdown was initiated at 2030 CST and Mode 3 was achieved at 2154 CST. All systems functioned as required during and following shutdown. The unit is proceeding to Mode 5. The licensee notified the NRC Resident Inspector.
ENS 545071 February 2020 16:29:00PerryNRC Region 3Core Spray

EN Revision Text: LOW PRESSURE CORE SPRAY INOPERABLE At 1150 EST on 2/1/2020, it was discovered that the Low Pressure Core Spray System was inoperable due to a divisional battery voltage being out-of-specification. Therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v). The Low Pressure Core Spray is a single train safety system in Modes 1, 2, and 3. Low Pressure Core Spray was restored to operable, restoring function at 1230 on 2/1/2020. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.

  • * * RETRACTION ON 03/16/2020 AT 1156 EDT FROM JOHN NAKEL TO BETHANY CECERE * * *

On February 01, 2020, event notification (EN-54507) was made to the NRC for Low Pressure Core Spray (LPCS) inoperability. This notification was made due to high DC bus voltages resulting in LPCS being declared inoperable which resulted in a loss of safety function. An Engineering Evaluation Request (EER) was performed to determine an upper limit for DC bus voltage. This EER determined that LPCS could perform its required functions with a voltage increase of up to 150V DC if the duration was not greater than two hours. The elevated voltage was experienced for approximately 59 minutes. The maximum voltage experienced was 147.07V DC. Therefore, LPCS remained operable and no loss of safety function existed. The NRC Resident Inspector has been briefed on the evaluation results and informed of this retraction." Notified R3DO (Hanna).

ENS 5450331 January 2020 09:46:00FitzPatrickNRC Region 1Reactor Protection System
Reactor Pressure Vessel
Main Condenser
Automatic ScramAt 0555 (EST), on January 31, 2020, James A. FitzPatrick was at 38 percent power when an automatic scram occurred as a result of a main turbine trip on high Reactor Pressure Vessel (RPV) water level. The plant was at reduced power in preparation for maintenance activities. The 'A' Reactor Feed Pump (RFP) was being removed from service when a perturbation in reactor water level reached the high RPV water level setpoint. This resulted in a main turbine trip and 'B' RFP trip. The automatic scram inserted all control rods. A subsequent low water level resulted in a successful Group 2 isolation. The plant is stable in Mode 3 with the 'B' RFP maintaining RPV water level. The initiation of the reactor protection systems (RPS) due to the automatic scram signal at critical power is reportable per 10 CFR 50.72(b)(2)(iv)(B) and 10 CFR 50.72(b)(3)(iv)(A). The general containment Group 2 isolations are reportable per 10 CFR 50.72(b)(3)(iv)(A). The licensee notified the NRC Resident Inspector, and the State and Local government for the scram. Decay heat is being removed via the main condenser.
ENS 5450230 January 2020 17:15:00South TexasNRC Region 4

On January 30, 2020, a non-licensed contractor supervisor had a confirmed positive for alcohol during a for-cause fitness-for-duty test. The employee's unescorted access to the plant has been terminated. The NRC Resident Inspector has been notified.

  • * * UPDATE ON 2/3/2020 AT 1223 EST FROM WILLIAM HERZOG TO BETHANY CECERE * * *

The initial NRC report wording was incorrect. Specifically, the non-licensed supervisory personnel violated the fitness for duty policy, they did not have a confirmed positive for-cause fitness-for-duty test. The title of this event is corrected. Notified R4DO (Taylor) and FFD Group.

ENS 5449527 January 2020 09:29:00SummerNRC Region 2

EN Revision Text: INADVERTENT ACTIVATION OF AN EARLY WARNING SIREN At 2354 EST, on January 26, 2020, officials with the State Emergency Operations Center and Newberry County, SC were notified of an apparent inadvertent actuation of a single siren in the VC Summer Early Warning Siren System (EWSS). (VC Summer Nuclear Station) VCSNS received a report of siren actuation from a local resident at approximately 2340 EST. The EWSS indication at the Emergency Operations Facility showed siren #35 had actuated. A reset of the EWSS was performed. VCSNS is working to confirm actual siren activation and troubleshoot the issue. This event is still under investigation. This is a non-emergency 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. The Licensee notified state and local agencies.

  • * * RETRACTION ON 1/29/2020 AT 1502 EST FROM HANK KIRKLAND TO ANDREW WAUGH * * *

The investigation of this event has concluded that EWSS siren #35 did not actuate. This conclusion was reached after interviewing residents who reside directly across the street from EWSS Siren #35, who confirmed that this siren did not actuate. Also, maintenance personnel investigations concluded that the local activation indication was erroneous, due to observed battery readings being normal. Had the siren actuated, its batteries would have been depleted or nearly depleted. The NRC Resident Inspector has been notified. Notified R2DO (Baptist).

ENS 5449122 January 2020 17:50:00HatchNRC Region 2At 2005 EST on January 21, 2020, Hatch Security was informed that a contract worker covered by 10 CFR 26.719(b) had been involved in a legal action as defined in 10 CFR 26.5. The contract worker's plant access has been suspended. The NRC Resident Inspector has been notified.
ENS 5448722 January 2020 04:34:00SequoyahNRC Region 2

EN Revision Text: CONTAINMENT RELIEF VALVES INOPERABLE At 22:18 (EST) on 1/21/20, it was discovered that all Unit 1 containment vacuum relief isolation valves were closed and all vacuum relief lines were simultaneously inoperable; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v). The isolation valves were opened and the vacuum relief valves were restored to operable.

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

  • * * UPDATE ON 02/20/2020 AT 1626 EST FROM FRANK SCHULTE TO BRIAN P. SMITH * * *

At 1549 (EST), February 20, 2020, a completed engineering evaluation of the condition initially reported on January 22, 2020 determined that the inoperability of the Sequoyah Unit 1 Containment Vacuum Relief System affected the ability to protect containment against an external pressure event. This condition is not bounded by existing design and licensing documents; however, it poses no impact to the health and safety of the public or plant personnel. The condition was resolved when isolation valves were opened on January 21, 2020 and the vacuum relief lines were restored to an operable status. Therefore, this event is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(ii)(B), "an unanalyzed condition that significantly degrades plant safety. Subsequent to the initial notification, continued evaluation of the reported condition has concluded that the isolation of the containment vacuum relief function did not prevent the fulfillment of a safety function that is needed to control the release of radioactive material; nor mitigate the consequences of an accident therefore this event is not reportable under 10 CFR 50.72(b)(3)(v), "Event or Condition that could have prevented fulfillment of a safety function. The NRC Resident has been notified. Notified R2DO (Musser)

ENS 5447413 January 2020 15:08:00FermiNRC Region 3A non-licensed contract employee supervisor tested positive for alcohol at another facility. The employee's access to Fermi 2 has been terminated. The NRC Resident Inspector has been notified.
ENS 5447213 January 2020 09:17:00McGuireNRC Region 2This 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. A planned modification to the Technical Support Center (TSC) power supplies started on January 13, 2020. The work activity includes installation of a permanent back-up diesel generator and rewiring of automatic and manual power transfer switches. The work duration is approximately three weeks. If an emergency is declared requiring TSC activation during this period, the Emergency Coordinator and the TSC staff will assemble and staff the alternate location in accordance with applicable site procedures. The Emergency Response Organization team has been notified of the TSC modification and the need to assemble and staff the alternate location during an emergency. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
ENS 544709 January 2020 19:25:00River BendNRC Region 4The Division I Control Building Chiller 'A' failed to start during post maintenance testing. By design, the Division II Control Building Chiller 'B' should have started automatically but did not. Operators then manually placed the Division I Control Building Chiller 'C' in service. This condition rendered both Divisions of the Control Building Air Conditioning System Inoperable. The applicable LCO was entered and exited 10 minutes later with all required actions and completion times met. The cause of the failure is not known at this time. The plant was at 100% power at the time of the event and is currently stable at 100% power. The NRC Resident Inspector has been notified.
ENS 544668 January 2020 02:49:00ColumbiaNRC Region 4On January 7, 2020, Columbia Generating Station (CGS) experienced an equipment failure that resulted in a loss of the seismic assessment instrumentation. This is being reported as a major loss of emergency assessment capability in accordance with regulation 10 CFR 50.72(b)(3)(xiii). No other plant systems were affected. Compensatory measures have been implemented and will remain in place until the seismic system has been restored. The NRC resident has been notified. Licensee received a design basis earthquake alarm, but no other local indication of seismic activity, nor on the U.S. Geological Survey website. Licensee compensatory measures include local readings on seismic instrumentation.
ENS 544657 January 2020 19:09:00OconeeNRC Region 2

At 1341(EST), on 01/07/20, it was discovered all trains of the Chilled Water System were simultaneously Inoperable; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v)(D). During this event, the Bravo train chiller was operating in a maintenance run and the temporary chiller was available and placed in service promptly to restore the safety function. The control room area cooling safety function was restored at time 1435 (EST) when one required train was declared Operable. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.

  • * * RETRACTION ON 1/23/2020 AT 1718 EST FROM JERRY COLLIER TO THOMAS KENDZIA * * *

The purpose of this notification is to retract a previous report made on January 7, 2020, at 1909 EST (EN#54465). A subsequent evaluation determined that the Bravo train chiller, which was running at the time of the event, would be able to perform its safety function and was operable at the time of the event. Therefore, there was no loss of safety function. The NRC Senior Resident Inspector has been notified. Notified R2DO (Coovert).

ENS 544634 January 2020 15:00:00HatchNRC Region 2Primary containmentAt 1109 (EST) on 01/04/2020, it was determined that the primary containment leakage rate did not meet value La, defined in 10 CFR 50, Appendix J, 'Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors'. An additional, tested valve has been closed to maintain leakage below maximum allowable leakage, La. 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 544601 January 2020 16:57:00Comanche PeakNRC Region 4Steam Generator
Auxiliary Feedwater
Main Condenser
Manual Scram

At 1253 (CST) Unit 2 Reactor was manually tripped due to a trip of both Main Feed Pumps. During an evolution to secure Circulating Water Pump 2-01, vacuum was reduced in the auxiliary condensers for both Main Feed Pumps causing both Main Feed Pumps to trip. Both Motor Driven and the Turbine Driven Auxiliary Feedwater Pumps started due to steam generator Lo-Lo levels.

Unit 2 is being maintained in Hot Standby (Mode 3) in accordance with Integrated Plant Operating Procedure IPO-0078. The Emergency Response Guideline Network has been exited. Decay heat is being rejected to the Main Condenser via the Steam Dump Valves. The licensee notified the NRC Resident Inspector.

ENS 5445727 December 2019 07:53:00MillstoneNRC Region 1Reactor Coolant System
Feedwater
Reactor Protection System
Auxiliary Feedwater
Manual Scram

This is a synopsis of initial information received via phone: On December 27, 2019, at 0705 EST, while Unit 2 was at 100 percent (Mode 1), the 'A' Main Feedwater Pump tripped due to an unknown cause. The reactor was manually tripped and is currently at zero (0) percent power (Mode 3). Decay heat is being removed via Auxiliary Feedwater. The 'B' Feedwater pump is operable. There was no impact on Unit 3. The licensee notified the NRC Resident Inspector. Additionally, Connecticut Department of Environmental Protection, Waterford Dispatch, and East Lyme Emergency Management Division will be notified.

  • * * UPDATE ON 12/27/2019 AT 1330 EST FROM JASON PARIS TO CATY NOLAN * * *

This is an update to NRC Event Number 54457. At 0704 EST, on 12/27/2019, with Millstone Unit 2 operating at 100 percent power, operators inserted a manual reactor trip. The trip was initiated due to a trip of the 'A' Main Feedwater Pump. The Auxiliary Feedwater System (AFW) automatically actuated as required. All control and shutdown rods fully inserted. All safety systems responded as designed. No primary or secondary safety valves actuated during or after the transient. Unit 2 is currently stable at normal operating pressure and temperature in Mode 3, Hot Standby. Reactor Coolant System (RCS) temperature is being maintained by the steam dump system with all Reactor Coolant Pumps (RCPs) in service. Main Feedwater has been secured, and Auxiliary Feedwater is in service. The electrical system is in normal alignment. There was no impact on Unit 3. There was no impact to the health and safety of the public or plant personnel. Due to Reactor Protection System (RPS) actuation while critical, this event was reported as a four hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B); and an eight hour non-emergency notification in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that resulted in a valid actuation of the AFW system. The licensee will notify the NRC Resident Inspector of the update. Notified R1DO (Cherubini).

ENS 5445218 December 2019 15:27:00FermiNRC Region 3Secondary containment
HVAC
Standby Gas Treatment System
On December 18, 2019, at 0908 EST, with the East and Center Reactor Building HVAC (RBHVAC) trains in service, secondary containment pressure degraded to the point where the Technical Specification (TS) requirement for secondary containment pressure was not met and secondary containment was declared inoperable. Secondary containment pressure did not meet the TS required limit for approximately four minutes. The maximum secondary containment pressure observed during that time was approximately 0.064 inches of vacuum water gauge. Secondary containment pressure was returned to within the TS operability limit of greater than or equal to 0.125 inches of vacuum water gauge (TS SR 3.6.4.1.1) by starting Division 1 of the Standby Gas Treatment System (SGTS). Secondary containment was declared Operable at 0912 EST. A modulating damper associated with the Center train of RBHVAC was identified as not properly controlling; an investigation is in progress. RBHVAC was manually secured to support problem identification and resolution. Secondary containment pressure is currently stable with Division 1 SGTS in service. There were no radiological releases associated with this event. Declaring secondary containment inoperable is reportable under 10 CFR 50.72(b)(3)(v)(C) as an event or condition that could have prevented the fulfillment of a safety function needed to control the release of radioactive material. The NRC Resident Inspector has been notified.
ENS 5444917 December 2019 21:10:00MillstoneNRC Region 1Emergency Diesel Generator
Residual Heat Removal
At 1929 EST, on 12/17/19, Millstone Unit 3 began preparations for shutting down the reactor as the 'A' Emergency Diesel Generator (EDG) could not be restored to operable status within the 14-day outage time, requiring a Technical Specification (Tech Spec) shutdown. Per Tech Spec 3.8.1.1., the reactor must be in Hot Standby in six (6) hours, and Cold Shutdown within the following 30 hours. Hot Standby is estimated by midnight, and Cold Shutdown by 1800 EST on 12/18/19. All other safety and shutdown systems are operable. Decay heat removal will be through the Shut Down Cooling and Residual Heat Removal systems. There was no impact to Unit 2. There was no impact to the health and safety of the public or plant personnel. The licensee notified the state of Connecticut, Waterford County, and the NRC Resident Inspector.
ENS 5444616 December 2019 09:12:00SequoyahNRC Region 2Emergency Diesel Generator

At 0358 EST, on 12/16/2019, with Unit 1 in Mode 1 at 100 (percent) power and Unit 2 in Mode 1 at 47 (percent) power, a valid actuation of the Emergency Diesel Generators (EDG) occurred. The reason for the emergency diesel generator auto start was that the normal feeder breaker from the 1C 6.9KV Unit Board to the 1B-B 6.9KV Shutdown Board (SDBD) tripped due to the breaker's 51G relay actuating causing an under-voltage signal on the 1B-B 6.9KV Shutdown Board. All 4 Emergency Diesel Generators automatically started as designed when the 6.9KV Shutdown Board under-voltage signal was received.

The 1B-B 6.9KV Shutdown Board was automatically energized from the 1B-B 6.9KV Diesel Generator. All required 6.9KV loads were sequenced back on to the 1B-B 6.9KV Shutdown Board as designed after the board was energized from its emergency diesel generator. The remainder of the electrical system is in normal alignment.

This event is being reported in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that resulted in a valid actuation of the Emergency Diesel Generators. There was no impact to the health and safety of the public or plant personnel. The NRC Senior Resident has been notified.

ENS 5443812 December 2019 08:14:00SequoyahNRC Region 2Reactor Coolant System
Feedwater
Reactor Protection System
Auxiliary Feedwater
Manual Scram

At 0432 EST, on 12/12/19, Sequoyah Unit 2 experienced a manual reactor trip. The trip was initiated due to a loss all number 3 Feedwater Heater Drain Tank pump flow; plant procedures directed a manual reactor trip if power is greater than 80 percent.

The Auxiliary Feedwater System (AFW) automatically actuated as required when the expected post trip feedwater isolation actuation actuated. Reactor Coolant System (RCS) temperature is being maintained by the steam dump system with all 4 Reactor Coolant Pumps (RCPs) in service. All control and shutdown rods fully inserted. All safety systems responded as designed. No primary or secondary safety valves actuated during or after the transient. Unit 2 is currently stable at normal operating temperature and normal operating pressure in Mode 3. The electrical system is in a normal alignment. There was no impact on U1. There was no impact to the health and safety of the public or plant personnel. Due to the Reactor Protection System (RPS) actuation while critical, this event is being reported as a four hour, non-emergency notification per 10CFR50.72(b)(2)(iv)(B) and an 8 hour non-emergency notification accordance with 10CFR50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the AFW system. The NRC Resident Inspector was notified.

ENS 5443711 December 2019 15:06:00SurryNRC Region 2Service water
Auxiliary Feedwater
On December 11, 2019, at 1356 EST, it was concluded that certain safety-related equipment is vulnerable to design basis tornado missiles which could render the equipment inoperable and not able to perform its design function. This applies to the following Technical Specification equipment: 1. Component cooling water piping for the 'A' spent fuel cooling water system heat exchanger. This heat exchanger is vulnerable to a horizontal missile traveling through the roll-up door, which would challenge operability of the Technical Specification required component cooling system equipment. 2. All three (3) emergency service water pumps and their diesel fuel oil supply tank. The emergency service water pumps and diesel fuel oil tank are vulnerable to a horizontal missile penetrating the missile screens. 3. Certain component cooling water system pump discharge piping is vulnerable from a vertical missile penetrating the auxiliary building roof. 4. The Unit 1 auxiliary feedwater (AFW) system pumps and the pump suction and discharge piping are vulnerable to a missile traveling through the screens on the sides and roof of the main steam valve house. This vulnerability also exists for the Unit 2 AFW. This condition puts Unit 1 and 2 into Technical Specification 3.01 which requires the units to be in hot shutdown within 6 hours and in cold shutdown within the following 30 hours. The NRC Resident Inspector has been notified.
ENS 5443310 December 2019 11:04:00Comanche PeakNRC Region 4

At 0920 CST on December 10, 2019, Comanche Peak began a planned modification on the Unit 1 Plant Computer System. During this modification, the ability to perform emergency assessment in the Technical Support Center (TSC) and the Emergency Operations Facility (EOF) will be impacted. Since the ability to perform emergency assessment is not expected to be restored within 72 hours, this is reportable per 10CFR50.72(b)(3)(xiii) as an event that results in a loss of emergency assessment capability.

During this modification, the Control Room will continue to have the ability to perform emergency assessment. If an Alert, Site Area Emergency, or General Emergency is declared during this modification, communicators dedicated to performing emergency assessment will be stationed in the Control Room, TSC, and EOF. The Plant Computer System modification is scheduled to be completed on December 22, 2019, and a follow-up ENS notification will be made once the Unit 1 Plant Computer System is declared functional.

The NRC Resident Inspector has been informed.

  • * * UPDATE ON 1/24/20 AT 1034 EST FROM THOMAS BOWDEN TO RODNEY CLAGG * * *

Licensee provided an update to inform that as of 0853 CST on 1/24/20, the modification is complete and the emergency assessment capabilities of the TSC and EOF have been restored. Notified R4DO (Silva)

ENS 5443110 December 2019 09:52:00Comanche PeakNRC Region 4Reactor Protection System
Auxiliary Feedwater

This report describes an invalid actuation of the Unit 2 Turbine Driven Auxiliary Feedwater Pump that occurred on October 31, 2019. This report is being made in accordance with 10CFR50.73(a)(1), which states, in part, 'In the case of an invalid actuation reported under 10CFR50.73(a)(2)(iv), other than actuation of the Reactor Protection System (RPS) when the reactor is critical, the licensee may, at its option, provide a telephone notification to the NRC Operations Center within 60 days after discovery of the event instead of submitting a written LER.'

On October 31, 2019, Comanche Peak Nuclear Power Plant Unit 2 was in Mode 1 operating at 100% power. At 1919 CDT, the Main Steam Line 2-01 steam supply valve to the TDAFWP opened due to a loss of continuity between the fuse supplying control power to the valve positioner and the fuse clips. Operators initiated a 50MW load reduction to maintain power less than 100%. The steam supply to the TDAFWP was closed, the TDAFWP was stopped, and the fuse clips were tightened. Unit 2 was returned to full power at 2055 CDT.

The specific train and system that actuated was the third AFW train on Unit 2. The train actuation was complete and during the TDAFWP start the system started and functioned correctly. The NRC Resident Inspector was notified.

ENS 5443010 December 2019 00:03:00Comanche PeakNRC Region 4Steam Generator1-RE-2328 Main Steam Line #1-04 MSL181 received an operate failure on loss of counts. At time 2126 (CDT), the radiation monitor was declared non-functional. With this radiation monitor non-functional, all of the emergency action levels for a steam generator tube rupture in steam generator 1-04 could neither be evaluated nor monitored. This unplanned condition is reportable as a loss of assessment capability per 10 CFR 50.72(b)(3)(xiii). Comanche Peak Nuclear Power Plant (CPNPP) has assurance of steam generator integrity and fuel cladding integrity. There is a negligible safety significance to the current condition from a public health and safety perspective. Additionally, compensatory measures are in place to assure adequate monitoring capability is available to implement the CPNPP emergency plan in the unlikely event of challenges to the steam generator or fuel cladding. The N16 radiation monitor serves as a backup with alarm function and additionally Radiation Protection technicians have been briefed on taking local readings with a Geiger-Mueller tube on MSL 1-04. Corrective actions are being pursued to restore 1-RE-2328 to functional status. The NRC Resident Inspector has been notified.
ENS 544255 December 2019 16:03:00CooperNRC Region 4The following was received via email from Cooper Nuclear Station: At 0810 (CST), on 12/5/19, Operations personnel discovered BLDG-DOOR-R209, FIRE DOOR BETWEEN CRITICAL SWITCHGEAR ROOMS F & G, was unlatched. The door was immediately latched upon discovery. Based on door logs, the door separating the two critical switchgear rooms was inadvertently left unlatched for approximately 5 minutes. This door is a Steam Exclusion Boundary (SEB) door. It is required to be closed and latched when the Auxiliary Steam Boiler is in service due to Auxiliary Steam piping passing through Critical Switchgear Room 'G'. If a steam line break was to occur with the door unlatched, steam could render both Critical Switchgear busses inoperable. This is being reported under 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition, and 10 CFR 50.72(b)(3)(v), Any 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 (B) remove residual heat and to (D) mitigate consequences of an accident. There was no impact on the health and safety of the public or plant personnel. The door closes automatically and appeared to have been left unlatched by the last person passing through. The door was tested and latches as required. The licensee notified the NRC Resident Inspector.