Semantic search
| Entered date | Site | Region | Reactor type | Event description | |
|---|---|---|---|---|---|
| ENS 56875 | 29 November 2023 17:02:00 | Indian Point | NRC Region 1 | Westinghouse PWR 4-Loop | The following information was provided by the licensee via email: This notification is being made per 10 CFR 50.72(b)(2)(xi), as a result of notifications made to State and local government agencies for the discovery of an oil sheen in the discharge canal outside Unit 3. The New York State Department of Environmental Conservation and Westchester County Department of Health were notified. No sheen was observed in the river or at the southern end of the discharge canal near the outfall gates. Clean up efforts are underway. The licensee will notify the NRC Project Manager. |
| ENS 56863 | 18 November 2023 02:51:00 | River Bend | NRC Region 4 | GE-6 | The following information was provided by the licensee via phone and email: On November 17, 2023, at 2215 CST, River Bend Station (RBS) was operating at 30 percent reactor power performing plant startup activities when an isolation of low-pressure feedwater string `A' occurred. The team entered applicable alternate operating procedures and inserted control rods to exit the restricted region of the power to flow map. Feedwater temperature continued to lower until it challenged the prohibited region of the AOP-0007 graph requiring a reactor scram. The team inserted a manual reactor scram at 2355 from 24 percent reactor power. All control rods fully inserted and there were no complications. All systems responded as designed. Currently RBS Unit 1 is stable with reactor level being maintained 10 to 51 inches with feed and condensate, and pressure being maintained 500 to 1090 psig using steam drains. 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 and 10 CFR 50.72(b)(3)(iv)(A) Specified System Actuation as result of Group 3 isolations. The NRC Senior Resident inspector has been notified. No radiological releases have occurred due to this event from the unit. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: The electric plant is in a normal lineup for current plant conditions with all emergency diesel generators available. The cause of the initial isolation of low-pressure feedwater string "A" is still under investigation. |
| ENS 56849 | 11 November 2023 00:23:00 | Waterford | NRC Region 4 | CE | The following information was provided by the licensee via email: At 1545 CST on November 10, 2023, personnel at Waterford Steam Electric Station Unit 3 determined that 19 conduits in the engineered safety features actuation system (ESFAS) auxiliary relay cabinets A and B did not have the required fire seals for bay separation. This condition meets the criteria involving an unanalyzed condition that significantly affects plant safety. The plant is currently defueled. Decay heat is being removed by normal spent fuel cooling system operations. ESFAS is not required to be operable in the current plant mode. This event is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(ii)(B) as an unanalyzed condition that significantly degrades plant safety. There was no impact to the health and safety of the public or plant personnel. The NRC Region 4 Branch Chief (Dixon) has been notified. |
| ENS 56834 | 5 November 2023 17:52:00 | Waterford | NRC Region 4 | CE | The following information was provided by the licensee via email: At 1033 CST on November 5, 2023, while in a refueling outage, it was determined that Waterford Steam Electric Station, Unit 3, did not meet the performance criteria for steam generator structural integrity in accordance with Technical Specification 6.5.9.b.1, Steam Generator Program, due to two tube failures in the number 1 steam generator. The condition was identified during performance of in-situ pressure testing. The affected tubes will be plugged. The plant is currently stable with all fuel in the spent fuel pool. Decay heat is being removed by normal spent fuel cooling system operation. This event is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(ii)(A) as a degraded condition. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. |
| ENS 56825 | 31 October 2023 14:20:00 | River Bend | NRC Region 4 | GE-6 | The following information was provided by the licensee via phone call and email: On October 31, 2023, at 0800 CDT, River Bend Station discovered that the results of a blind performance sample provided to an Health and Human Services (HHS)-certified testing facility were inaccurate (false negative). This report is being made in accordance with 10 CFR 26.719(c)(3). The HHS-certified testing facility has been informed of the error. The licensee notified the NRC resident inspector.
On November 1, 2023, River Bend Station personnel were informed by the HHS-certified testing facility that the cut-off levels used for analysis of the performance testing sample in question were the correct (higher) cut-off levels currently being used by the licensee. This resulted in a correct negative test. The performance testing sample sent to the HHS-certified testing facility was purchased for use based on the new lower cut-off levels in accordance with the new fit for duty (FFD) rule being implemented by the licensee on November 6, 2023. Because the higher confirmatory cut-off levels were used at the HHS-certified testing facility, the results provided were correct. The NRC Resident Inspector has been notified." Notified R1DO (Eve) and FFD Group (email) |
| ENS 56811 | 22 October 2023 16:40:00 | Cooper | NRC Region 4 | GE-4 | The following information was provided by the licensee via fax and phone: On October 22, 2023, at 1149 CDT, with the reactor at 100 percent core thermal power and steady state conditions, the Cooper Nuclear Station secondary containment differential pressure exceeded the Technical Specification (TS) Surveillance Requirement (SR) 3.6.4.1.1 limit of -0.25 inches water gauge. The condition existed for approximately 80 seconds until the reactor building ventilation system responded to restore differential pressure to normal. Investigations identified a hinged duct access hatch found open. The hatch was closed and latched, and ventilation system parameters were returned to normal. There were no radiological releases associated with this event. Declaring secondary containment inoperable as a result of not meeting TS SR 3.6.4.1.1 is reportable under 10 CFR 50.72(b)(3)(v)(C) and (D) as an event or condition that could have prevented the fulfillment of a safety function needed to control the release of radioactive material and mitigate the consequences of an accident. The NRC Senior Resident Inspector has been informed. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: At the time the licensee notified the NRC Headquarters Operations Officer, the cause of the hinged access duct being open had not been determined. This event has been added to the licensee's corrective action program. |
| ENS 56786 | 10 October 2023 19:44:00 | Cooper | NRC Region 4 | GE-4 | The following information was provided by the licensee via fax: On October 10, 2023, at 1553 CDT, Cooper Nuclear Station (CNS) was notified of a spurious actuation of a single alert notification system siren in Nemaha, Nebraska. The CNS Emergency Alert System (EAS) was not activated. The actuation occurred during siren testing conducted at approximately 1545 CDT. No emergency conditions are present at Cooper Nuclear Station. A press release from Nebraska Public Power District is not planned at this time. This condition is reportable under 10CFR 50.72(b)(2)(xi) for any event or situation for which a news release is planned or notification to other government agencies has been or will be made which is related to heightened public or government concern. The NRC Senior Resident Inspector has been notified. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: Offsite notification was to local Nemaha County Emergency Management. |
| ENS 56727 | 7 September 2023 23:35:00 | Arkansas Nuclear | NRC Region 4 | CE B&W-L-LP | The following information was provided by the licensee via email: On September 7 at 1230 CDT, Arkansas Nuclear One personnel identified 5 bottles of vanilla extract in kitchen areas located inside the Protected Area. A total of 5 bottles were identified. The bottles ranged in sizes of 1 to 4 ounces. Ingredients were listed as vanilla extracts in water and alcohol. The percentage by volume of alcohol varied from 13 - 41 percent. This report satisfied the reporting criteria of 10 CFR 26.719. The NRC Resident Inspector has been notified. |
| ENS 56724 | 7 September 2023 10:01:00 | Grand Gulf | NRC Region 4 | GE-6 | The following information was provided by the licensee via email: On September 6 at 15:00 CDT, Grand Gulf Nuclear Station personnel identified a bottle of vanilla extract in a kitchen area located within the Protected Area. Ingredients were listed as 'pure vanilla extract in water and alcohol. The percentage by volume of alcohol was not specified. It was subsequently determined that the alcohol by volume was likely 35 percent. The NRC Resident Inspector has been notified. |
| ENS 56722 | 6 September 2023 19:22:00 | Waterford | NRC Region 4 | CE | The following information was provided by the licensee via email: A supplemental contract supervisor had a confirmed positive for an illegal substance during a random fitness-for-duty test. The employee's access to the plant has been terminated. |
| ENS 56696 | 24 August 2023 21:30:00 | Grand Gulf | NRC Region 4 | GE-6 | The following information was provided by the licensee via email: On August 23, 2023 at 2100 CDT, Grand Gulf Nuclear Station was notified that a non-licensed supervisor violated the station's Fitness for Duty policy. The employee's unescorted access at Grand Gulf Nuclear Station has been terminated. This event was determined to be reportable under 10 CFR 26.719(b)(2)(ii). The NRC Resident Inspector has been notified. |
| ENS 56644 | 30 July 2023 17:25:00 | Waterford | NRC Region 4 | CE | The following information was provided by the licensee via email: On July 30, 2023 at 1119 CDT, Waterford Steam Electric Station Unit 3 declared the control room envelope inoperable in accordance with technical specification (TS) 3.7.6.1 due to the control room envelope doors failing a door seal smoke test creating a breach in the control room envelope. Operations entered TS 3.7.6.1 Action b. Mitigating actions were implemented and tested satisfactorily by 1215 CDT. There was no impact on the health and safety of the public or plant personnel. This event is reportable pursuant to 10 CFR 50.72(b)(3)(v)(D), as an event or condition that could have prevented fulfillment of a safety function of structures or systems that are needed to mitigate the consequences of an accident, due to the control room envelope being inoperable. The NRC Resident Inspector has been notified.
The original operability determination of inoperable was made based on a conservative evaluation that with presence of smoke in-leakage through Door 261 and 262, the CRE boundary could not perform its safety function. A more detailed engineering evaluation was subsequently performed. No maintenance or intrusive testing was performed on the doors after initial test failure. As documented in version 2 operability determination for condition report WF3-2023-14604, the CRE boundary remained intact for the condition identified and was able to fulfill its safety function. The licensee has notified the NRC Resident Inspector. Notified R4DO (Warnick). |
| ENS 56641 | 26 July 2023 09:10:00 | River Bend | NRC Region 4 | GE-6 | The following information is a synopsis provided by the licensee via email: River Bend Station completed an internal Part 21 evaluation concerning a motor driven relay that failed pre-installation testing due to a buildup of corrosion between the rotor and relay core. The relay was planned for use in the Remote Shutdown System. The NRC Resident has been notified. A written notification will be provided within 30 days. Affected known plants include only River Bend at the time of the notification. |
| ENS 56598 | 29 June 2023 15:41:00 | Grand Gulf | NRC Region 4 | GE-6 | The following information was provided by the licensee via email: A non-licensed supervisor had a confirmed positive for alcohol during a random fitness-for-duty test. The employee's access to the plant has been terminated. The NRC Resident Inspector has been notified. |
| ENS 56509 | 8 May 2023 06:25:00 | Cooper | NRC Region 4 | GE-4 | The following information was provided by the licensee via fax: At time 0207 CDT, Cooper Nuclear Station (CNS) entered Technical Specification (Limiting Condition for Operation) LCO 3.0.3 due to declaring core spray subsystems A and B inoperable. This declaration was based on an issue with relays installed from the same manufacturing batch. The ability of the relays to function correctly to annunciate loss of logic power was called into question and they were declared inoperable. The plant has initiated actions to repair/replace affected relays. This event is reportable under 10 CFR 50.72(b)(2)(i) as an initiation of any nuclear plant shutdown required by Technical Specifications. In addition, this event Is reportable under 10 CFR 50.72(b)(3)(v) as a condition that could have prevented the fulfillment of a safety function for the core spray systems. NRC Resident Inspector was notified.
The following information was provided by the licensee via email: Technical Specification LCO 3.0.3 was exited at 0805 CDT on May 8, 2023. A reasonable expectation of operability was developed for the core spray subsystems A and B. 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 45 percent. Reactor power is currently at 55 percent at the time of notification. Notified R4DO (Werner) via email.
The following information was provided by the licensee via email: CNS is retracting the 8-hour 10 CFR 50.72(b)(3)(v) non-emergency notification, for a condition that could have prevented the fulfillment of a safety function, made on May 8, 2023, at 0207 CDT (EN# 56509). Subsequent evaluation concluded that the core spray subsystems remained operable in accordance with the Technical Specifications Requirements 3.5.1, ECCS - Operating. As a result of the core spray system remaining operable, no loss of safety function occurred. The NRC Senior Resident Inspector has been notified. Notified R4DO (Werner). |
| ENS 56503 | 4 May 2023 12:25:00 | Indian Point | NRC Region 1 | Westinghouse PWR 4-Loop | The following summary was provided by the licensee via phone: On May 4, 2023 at 1145 EDT, the licensee found contact dose rates of 215 and 555 millirem-per-hour at 2 separate spots on the top of an exclusive use package during receipt survey. These dose rates are above the 200 millirem-per-hour allowable. No loose surface contamination was identified. The package contains tools from Holtec and was intact on delivery. The package has subsequently been secured in a locked radiation storage building. No overexposure or unauthorized exposure resulted to plant personnel. The licensee suspects shielding, internal to the package, may have shifted and the licensee will investigate further. Dose rates at one foot from the package were recorded at 65 millirem per hour. |
| ENS 56501 | 2 May 2023 22:41:00 | Palisades | NRC Region 3 | CE | The following information was provided by the licensee via email: At approximately 1500 (EDT) on 5/2/2023, it was determined that the commercial telecommunications capacity was lost to the Palisades Nuclear Plant (PNP) control room and technical support center due to an issue with the telecommunications provider. After discovery of the condition it was discovered that this loss also included the emergency notification system (ENS). Communications link via the satellite phone was tested satisfactorly. In addition, if needed, the satellite phone would be used to initiate call-out of the emergency response organization. The condition did not affect the ENS or commercial telecommunications capabilities at the offsite Emergency Operations Facility. The telecommunications provider has not provided an estimated repair time. PNP will be notifying the NRC resident inspector.
The following information was provided by the licensee via email: This notification is being made to retract event EN 56501 that was reported on May 02, 2023. Based on further investigation, the Emergency Plan and Emergency Implementing Procedures provide an acceptable alternative routine communication system, which is satellite phones, for communicating with Federal, State, and local offsite agencies, that are in addition to the primary commercial telephone system. It was determined that no actual or potential loss of offsite communications capability existed per 10 CFR 50.72(b)(3)(xiii). This is consistent with NUREG 1022, Revision 3, Supplement 1, 'Event Report Guidelines 10 CFR 50.72(b)(3)(xiii),' and NEI 13-01, Revision 0, 'Reportable Action Levels for Loss of Emergency Preparedness Capabilities.' The NRC Decommissioning Inspector has been notified of the retraction. Commercial telecommunications to the plant were restored at approximately 0600 EDT on 5/3/2023. Notified R3DO (Orlikowski) |
| ENS 56491 | 26 April 2023 16:30:00 | River Bend | NRC Region 4 | GE-6 | A non-licensed supervisor had a confirmed positive for alcohol during a random fitness-for-duty test. The employee's access to the plant has been terminated. The NRC Resident Inspector has been notified. |
| ENS 56428 | 23 March 2023 16:46:00 | River Bend | NRC Region 4 | GE-6 | A non-licensed contract supervisor was confirmed to have violated the FFD policy by attempting to subvert the testing process. The individual's authorization for site access was immediately terminated. The licensee notified the R4 Branch Chief (Josey)
The following information was provided by the licensee via email: The Medical Review Officer (MRO) was provided with additional information on the collection process in question. Based on this additional information, the MRO was unable to conclude with a high degree of certainty that an attempt to subvert the FFD collection process had occurred." Notified R4DO (Gaddy) and via email the FFD Group. |
| ENS 56403 | 10 March 2023 07:25:00 | Waterford | NRC Region 4 | CE | The following information was provided by the licensee via email: On 03/09/2023 at 2200 CST, Waterford (Unit) 3 entered OP-901-111, Reactor Coolant System Leakage, and OP-901-403, High Activity In Containment, due to elevated reactor coolant system (RCS) leakage in containment. On 03/10/2023, at 0030 Operations entered Technical Specification 3.4.5.2 action (c) due to unidentified leakage exceeding 1 gallon per minute (gpm). Technical Specification 3.4.5.2 action (c) requires reducing the leakage rate to within limits within 4 hours or be in at least hot standby within the next 6 hours and in cold shutdown within the following 30 hours. On 03/10/2023 at 0237 the plant discovered an unisolable RCS leak in the reactor coolant pump 1B cubicle and initiated action to complete a plant shutdown required by Technical Specifications. This event is being reported as a 4-hour report in accordance with 10 CFR 50.72(b)(2)(i) as the initiation of plant shutdown required by technical specifications. Reactor was tripped at 0521 CST on 3/10/2023. |
| ENS 56390 | 5 March 2023 03:02:00 | River Bend | NRC Region 4 | GE-6 | The following information was provided by the licensee via email: At 2300 CST on March 4, 2023, River Bend Station (RBS) was shut down in Mode 5 when an individual was transported offsite for treatment at an offsite medical facility. Due to the nature of the medical condition, the individual was not thoroughly surveyed prior to being transported offsite. Follow-up surveys performed by radiation protection technicians identified no contamination of the worker or of the ambulance and response personnel. This is an eight-hour notification, non-emergency for the transportation of a contaminated person offsite. This event is reportable in accordance with 10 CFR 50.72(b)(3)(xii). The NRC Resident Inspector has been notified. |
| ENS 56351 | 14 February 2023 14:40:00 | Arkansas Nuclear | NRC Region 4 | B&W-L-LP | The following information was provided by the licensee via email: On February 14, 2023 at 1103 CST, Arkansas Nuclear One, Unit 1, (ANO-1) automatically tripped on reactor protection system actuation due to two reactor coolant pumps tripping. ANO-1 is currently stable in MODE 3 (Hot Standby) maintaining reactor coolant system pressure and temperature with main feedwater and steaming to the condenser. No additional safety system actuations occurred. All immediate actions were completed satisfactorily. There are no indications of a radiological release on either unit as a result of this event. This report satisfies the reporting criteria of 10 CFR 50.72(b)(2)(iv)(B) and 10 CFR 50.72(b)(3)(iv)(A) for the reactor protection system actuation. The NRC Senior Resident Inspector has been notified. Unit 2 was not affected. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: The licensee is investigating the cause of the two reactor coolant pump trips. |
| ENS 56346 | 9 February 2023 15:15:00 | Cooper | NRC Region 4 | GE-4 | The following information was provided by the licensee via fax: A licensed operator had a confirmed positive for alcohol during a for-cause fitness-for-duty test. The employee's access to the plant has been terminated. The NRC Resident Inspector has been notified. |
| ENS 56282 | 20 December 2022 00:24:00 | Grand Gulf | NRC Region 4 | GE-6 | The following information was provided by the licensee via email: At 2101 (CST) on December 19, 2022, a manual reactor scram was initiated at Grand Gulf Nuclear Station (GGNS). Following the reactor scram, the high pressure core spray (HPCS) system was used to maintain reactor water level. The manual (reactor protection system) RPS actuation is being reported in accordance with 10 CFR 50.72(b)(2) and the HPCS actuation is being reported in accordance with 10 CFR 50.72(b)(3). At 2058, GGNS experienced a loss of a condensate booster pump. At 2101, the `A' reactor feedwater pump tripped and the reactor was manually scrammed. All control rods were fully inserted into the core. At 2104, the `B' reactor feedwater pump tripped and HPCS was manually started. HPCS was manually injected to maintain reactor water level at 2121. The `A' reactor feedwater pump was successfully restarted at 2126. GGNS is currently in Mode 3. Reactor level is being maintained with the `A' reactor feedwater pump and pressure is being maintained with the turbine bypass valves. The NRC Resident Inspector was notified. |
| ENS 56278 | 17 December 2022 04:03:00 | Cooper | NRC Region 4 | GE-4 | The following information was provided by the licensee via email: On December 16, 2022 at 2351 CST, with the Unit in Mode 1 at 13 percent power, a manual scram was inserted due to lowering Reactor Pressure Vessel (RPV) pressure, which occurred following an unexpected opening of Main Turbine Bypass Valve 1. All control rods fully inserted. Following actuation of the manual scram, RPV pressure lowered, resulting in an automatic Primary Containment lsolation (PCIS) Group 1 isolation (expected response). The main steam isolation valves and steam line drain valves all closed. The Group 1 (isolation) has been reset allowing RPV pressure control with steam line drains to the main condenser. All systems responded as designed. The plant is stable in Mode 3. Investigation of the bypass valve opening is ongoing. This event is reportable under 10 CFR 50.72(b)(2)(iv)(B) RPS Actuation and 50.72(b)(3)(iv)(A) Specified System Actuation. There was no impact on health and safety of the public or plant personnel. The NRC Senior Resident Inspector has been notified. |
| ENS 56220 | 13 November 2022 04:01:00 | Cooper | NRC Region 4 | GE-4 | The following information was provided by the licensee email: On November 12, 2022, at 2319 CST, an actuation of the reactor protection system (RPS) initiated a full scram. The plant was in Mode 2, reactor pressure was 149 pounds. The high pressure coolant injection (HPCI) injection valve, HPCI-MOV-MO19, opened and injected cold water into the reactor vessel while HPCI system testing was in progress. The cause is still under investigation. All control rods inserted. Plant is currently in Mode 3 and stable. All systems operated as designed with no Primary Containment Isolation System group isolations. This event is being reported under two event classifications: 50. 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. 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) of this section except when the actuation results from and is part of a pre-planned sequence during testing or reactor operation. The NRC Resident has been informed. |
| ENS 56214 | 9 November 2022 15:37:00 | Waterford | NRC Region 4 | CE | A non-licensed supervisor had a confirmed positive during a random fitness-for-duty test. The employee's access to the plant has been terminated. The NRC Resident Inspector has been notified. |
| ENS 56202 | 3 November 2022 14:05:00 | Waterford | NRC Region 4 | CE | The following information was provided by the licensee via email: This 60-day telephonic notification is being made in lieu of a licensee event report submittal as allowed by 10 CFR 50.73(a)(1). This notification is made pursuant to 10 CFR 50.73(a)(2)(iv)(A) to provide information pertaining to an invalid engineered safety feature actuation signal. On September 6, 2022, at Waterford 3, while performing a plant protection system (PPS) power supply check, technicians observed an abnormally high voltage output. When the technicians opened the PPS bay cabinet door to adjust the voltage, they then observed low voltage indications. The direct cause of this issue is believed to be vibration induced relay chattering or an intermittent connection issue when opening the rear doors of PPS cabinets. This resulted in half the logic being met for the Engineered Safety Feature Actuation Signal (ESFAS) signals to fully actuate. The ESFAS signal opened the following valves: EFW-228A (EFW to SG 1 Primary Isolation), EFW-229A (EFW to SG 1 Backup Isolation), EFW-228B (EFW to SG 2 Primary Isolation) and EFW-229B (EFW to SG 2 Backup Isolation). This was a partial actuation of ESFAS. Affected plant systems functioned successfully. The inadvertent actuation was caused by a spurious signal and was not a valid signal resulting from actual parameter inputs. The 1992 Statements of Consideration define an invalid signal to include spurious signals including jarring of a cabinet door. In accordance with 10 CFR 50.73(a)(1) a telephone notification is being made in lieu of submitting a written licensee event report. The NRC Senior Resident Inspector has been notified. These events did not result in any adverse impact to the health and safety of the public. |
| ENS 56192 | 31 October 2022 15:29:00 | Grand Gulf | NRC Region 4 | The following information was provided by the licensee via email: On February 22, 2021 while in Mode 1 and at 100 percent power, Grand Gulf Nuclear Station (GGNS) identified through surveillance testing that the 208 foot elevation outer containment personnel airlock door failed its technical specification leakage test. Analysis indicated that the airlock equalizing valves were leaking due to lack of lubrication during installation. Subsequent analysis determined that the lubrication was to have been performed during a vendor's qualification / dedication process. GGNS completed a substantial safety hazard Evaluation and determined that the failure to lubricate the valve components constituted a substantial safety hazard. The NRC Resident (Inspector) has been notified. This is a non-emergency notification required by 10 CFR 21.21(d)(3)(i). A written notification will be provided within 30 days. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: This condition has been corrected. This report is submitted to meet 10 CFR Part 21 reporting requirements. | |
| ENS 56185 | 27 October 2022 19:49:00 | Grand Gulf | NRC Region 4 | GE-6 | The following information was provided by the licensee via email: At 1228 CDT on October 27, 2022, Grand Gulf Nuclear Station (GGNS) was in Mode 1 at 88 percent power when a failure of a draw down surveillance resulted in the loss of secondary containment. During the performance of the surveillance GGNS was unable to maintain secondary containment pressure, as required by Technical Specification Surveillance Requirement 3.6.4.1.4, greater than or equal to 0.266 inches of water vacuum for 1 hour at a flow rate of less than or equal to 4000 cfm. The test was secured. Secondary containment was declared inoperable and Technical Specification 3.6.4.1 A.1 was entered at 1228 CDT. Secondary containment was restored to operable status at 1240 CDT by restoring the configuration to a previously known operable condition. This event is being reported as an event or condition that could have prevented the fulfillment of a safety function. The NRC Resident Inspector was notified. |
| ENS 56174 | 22 October 2022 17:36:00 | Cooper | NRC Region 4 | GE-4 | The following information was provided by the licensee via fax: During Mode 5 Refueling operations, while attempting to establish flow through the Fuel Pool Cooling system filter demineralizers, an air operated valve to a radioactive waste tank failed to close automatically. This caused the Fuel Pool Cooling system to pump water from the Skimmer Surge Tanks (SST) to the radioactive liquid waste system. In response to the loss of inventory from the SSTs, the Control Room operating crew started Core Spray Pump A to restore normal operating level In the SST. This prevented the loss of the Fuel Pool Cooling/Alternate Decay Heat Removal system which was the only in service system meeting the safety function of decay heat removal. Core Spray Pump A was used for Injection for less than 3 minutes. This is reportable as a discharge of ECCS into the RCS in response to an event, but not part of a pre-planned sequence under 10 CFR 50.72(b)(2)(iv)(A) and actuation of a specified system under 10 CFR 50.72(b)(3)(Iv)(A). The resident inspector has been notified. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: Licensee reported approximately 6000-7000 gallons of water was injected into the RCS. The stuck open air operated valve was closed. Proceeding with refueling outage operations. |
| ENS 56171 | 20 October 2022 11:31:00 | Grand Gulf | NRC Region 4 | GE-6 | The following information was provided by the licensee via email: At 0427 CDT on October 20, 2022, Grand Gulf Nuclear Station (GGNS) was in Mode 1 at 100 percent power when a failure of a draw down surveillance resulted in the loss of secondary containment. During the performance of the surveillance GGNS was unable to maintain secondary containment pressure, as required by Technical Specification Surveillance Requirement 3.6.4.1.4, greater than or equal to 0.266 inches of water vacuum for 1 hour at a flow rate of less than or equal to 4000cfm. The test was secured. Secondary containment was declared inoperable and Technical Specification 3.6.4.1 A.1 was entered at 0427 CDT. Secondary containment was restored to operable status at 0520 CDT by restoring the configuration to a previously known operable condition. This event is being reported as an event or condition that could have prevented the fulfillment of a safety function. The NRC Resident Inspector was notified. |
| ENS 56152 | 7 October 2022 05:41:00 | Cooper | NRC Region 4 | GE-4 | The following information was provided by the licensee via fax: On 10/7/2022 at 0050 CDT, a potentially contaminated individual was transported off-site via ambulance to a local hospital. Due to the nature of the medical condition, an initial on-site survey for radioactive contamination was not performed prior to transport. Prior to arrival at the hospital, it was confirmed the individual and (the individual's) clothing were not radiologically contaminated. Follow-up surveys performed by radiation technicians identified no radiological contamination of the ambulance and response personnel. This event is being reported per 50.72(b)(3)(xii) - 'Any event requiring the transport of a radioactively contaminated person to an offsite medical facility for treatment.' The NRC Resident Inspector has been notified. |
| ENS 56140 | 4 October 2022 15:54:00 | Arkansas Nuclear | NRC Region 4 | CE B&W-L-LP | A non-licensed supervisor had a confirmed positive during a random fitness-for-duty test. The employee's access to the plant has been terminated. The NRC Resident Inspector has been notified. |
| ENS 56136 | 1 October 2022 00:08:00 | Arkansas Nuclear | NRC Region 4 | CE B&W-L-LP | A supplemental supervisor violated the station's FFD policy. The individuals access to the plant has been terminated. The licensee notified the NRC Senior Resident Inspector. |
| ENS 56118 | 19 September 2022 19:29:00 | Grand Gulf | NRC Region 4 | GE-6 | The following information was provided by the licensee via email: At approximately 1520 CDT on September 19, 2022, Grand Gulf Nuclear Station (GGNS) requested transport for treatment of a non-responsive individual, a contract employee, to an offsite medical facility. The offsite medical facility notified GGNS at approximately 1630 CDT that the individual had been declared deceased. The fatality was not work-related, and the individual was outside of the Radiological Control Area. This is a four-hour non-emergency notification in accordance with 10 CFR 50.72(b)(2)(xi) related to the notification of a government agency. The contractor's employee will be notifying the Occupational Safety and Health Administration. The NRC Senior Resident Inspector has been notified. |
| ENS 56116 | 19 September 2022 08:37:00 | River Bend | NRC Region 4 | GE-6 | The following information was provided by the licensee via email: At 0132 CDT on September 19, 2022, River Bend Station (RBS) was operating at 100% power when the high pressure core spray (HPCS) system was declared inoperable in accordance with technical specification 3.8.9, condition E (declare HPCS and standby service water system pump 2C inoperable immediately) due to a E22-S003, HPCS transformer feeder malfunction. The HPCS is a single train system at RBS, therefore this event is being reported in accordance with 10 CFR 50.72(b)(3)(v)(D) as an event or condition that could have prevented the fulfilment of a safety function. The reactor core isolation cooling system has been verified to be operable. The NRC Resident Inspector has been notified. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: RBS has entered a 14-day limiting condition for operation due to the loss of HPCS and they have upgraded their on-line plant risk model to "yellow". |
| ENS 56059 | 20 August 2022 02:11:00 | Grand Gulf | NRC Region 4 | GE-6 | The following information was provided by the licensee via fax or email: At 2342 CDT on August 19, 2022, with Grand Gulf Nuclear Station in Mode 1 and at 40 percent power, the station initiated a normal shutdown to comply with its Technical Specifications (TS). The station entered Mode 3 at 0000 CDT August 20, 2022 to comply with (LCO) 3.5.1 Condition G Action G.1 due to the condition reported to NRC previously (EN 56058). This event is being reported under 10 CFR 50.72(b)(2)(i) as a shutdown required by the plant's technical specifications. The NRC Senior Resident Inspector was notified. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: The plant is now in a 36-hour LCO to be in Mode 4 due to Low Low Set Valves inoperability per TS 3.6.1.6.
Grand Gulf Nuclear Station (GGNS) is performing this notification to retract event EN 56059 that was reported on August 20, 2022. Previously, GGNS notified the NRC that it had initiated a shutdown required by Technical Specifications to comply with Limiting Condition of Operation (LCO) 3.5.1 Condition G.1 due to the inoperability of four Automatic Depressurization System (ADS) valves. Following the shutdown, GGNS completed walkdowns and determined that the condition affected only one ADS valve. As a result, the shutdown to satisfy the required actions of TS LCO 3.5.1 Condition G.1 was not required. The NRC Resident Inspector has been notified of the retraction. R4DO (Kellar) was notified. |
| ENS 56058 | 19 August 2022 20:46:00 | Grand Gulf | NRC Region 4 | GE-6 | The following information was provided by the licensee via email: At 1215 CDT on 8/19/2022, with Grand Gulf Nuclear Station in Mode 1 and at 100 percent power, four Automatic Depressurization System (ADS) valves were rendered inoperable due to a loss of system pressure. The station entered Technical Specification 3.5.1 Condition G. This event is being reported under 10 CFR 50.72(b)(3)(v)(D) as an event or condition that could have prevented the fulfillment of a safety function. There were no other systems affected as a result of this condition. The NRC Senior Resident Inspector was notified. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: Plans are to remain in Mode 1 until corrected or until driven by the Technical Specifications to shut down (12-hour LCO from 1215 CDT on 8/19/2022).
Grand Gulf Nuclear Station (GGNS) is performing this notification to retract event EN 56058 that was reported on August 19, 2022. Previously, GGNS notified the NRC that four Automatic Depressurization System (ADS) valves were inoperable due to a loss of system pressure. Based upon further investigation, the condition reported in EN 56058 was found to affect only a single ADS valve. As a result, it was determined that an event or condition that could have prevented the fulfillment of a safety function did not exist at GGNS. Sufficient redundancy existed to perform the safety function. The NRC Resident Inspector has been notified of the retraction. R4DO (Kellar) was notified. |
| ENS 55981 | 7 July 2022 22:49:00 | Cooper | NRC Region 4 | GE-4 | The following information was provided by the licensee via phone and fax: On 7/7/2022, at 0740 CDT, the National Weather Service reported to Cooper Nuclear Station that the NAWAS ((National Warning System)) radio tower near Shubert, Nebraska would neither transmit nor receive. The Shubert Tower transmitter activates the EAS ((Emergency Alert System))/Tone Alert Radios used for public notification. Additional information from the National Weather Service received 7/7/2022 at 1601 (CDT) determined that the Shubert Tower transmitter is non-functional and would not likely be repaired within 24 hours. The backup notification system has been verified to be available throughout this period. This is considered to be a major loss of the Public Prompt Notification System capability. The primary notification system is not expected to be restored to service within 24 hours, and therefore this condition is reportable under 10 CFR 50.72(b)(3)(xiii), since the backup alerting methods do not meet the primary system design objective. The backup notification system is available to use for notifications if needed. The NRC Senior Resident has been informed. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: The backup notification system has to be manually activated. |
| ENS 55973 | 30 June 2022 18:07:00 | Grand Gulf | NRC Region 4 | GE-6 | The following information was provided by the licensee via phone and email: At 1445 (CDT) on June 30, 2022, with Grand Gulf Nuclear Station in Mode 1 and at 100 percent power, the reactor was manually scrammed due to the loss of balance of plant (BOP) transformer 23. All control rods fully inserted into the core and all systems responded appropriately. Reactor level is being maintained with condensate and feedwater. Reactor pressure is being maintained with turbine bypass valves. The cause of the loss of BOP transformer 23 is under investigation at this time. Standby Service Water 'A' and 'B' were manually initiated to supply cooling to Control Room A/C, ESF switchgear room coolers, and plant auxiliary loads. This event is being reported under 10 CFR 50.72(b)(2)(iv)(B) as an event or condition that resulted in actuation of the Reactor Protection System and 10 CFR 50.72(b)(3)(iv)(A) due to the actuation of Standby Service Water. The NRC Senior Resident Inspector was notified. |
| ENS 55963 | 25 June 2022 00:44:00 | Waterford | NRC Region 4 | CE | The following information was provided by the licensee via email: At 2012 CDT, Waterford 3 Steam Electric Station, Unit 3 was operating at 100 percent power when an automatic reactor trip occurred due to Main Steam Isolation Valve MS-124B going closed unexpectedly. Subsequently, both main feedwater isolation valves shut. Emergency Feedwater (EFW) was automatically actuated. Preliminary evaluation indicates that all plant systems functioned normally after the reactor trip. The unit is currently stable in Mode 3. All control rods fully inserted as expected and all other plant equipment functioned as expected. This was an uncomplicated scram. This event is being reported as a 4-hour non-emergency notification in accordance with 10 CFR 50.72(b)(2)(iv)(B) as an actuation of the reactor protection system (RPS) when the reactor is critical and as an 8-hour non-emergency notification in accordance with 10 CFR 50.72(b)(3)(iv)(A) as valid actuation of the EFW system. The NRC Resident Inspector has been notified. |
| ENS 55915 | 26 May 2022 10:34:00 | Grand Gulf | NRC Region 4 | GE-6 | The following information was provided by the licensee via phone and email: On May 26, 2022, at 0753 CDT, the Grand Gulf Nuclear Station was notified of a spurious actuation of a single Alert Notification System siren in Tensas Parish, Louisiana. The actuation occurred during siren testing conducted at approximately 0630 CDT - no emergency conditions are present at Grand Gulf Nuclear Station. A press release from Entergy is not planned at this time. This condition is reportable under 10 CFR 50.72(b)(2)(xi) as a notification of an offsite government agency. The NRC Senior Resident Inspector has been notified. |
| ENS 55907 | 23 May 2022 11:23:00 | Cooper | NRC Region 4 | GE-4 | The following information was provided by the licensee via email: On May 23, 2022, at 0455 CST, Cooper Nuclear Station experienced a spike in Secondary Containment differential pressure which exceeded the Technical Specifications Surveillance Requirements 3.6.4.1.1 limit of -0.25 inches of water gauge. Secondary Containment differential pressure restored to Technical Specification limits within two minutes and further investigation is ongoing. This unplanned Secondary Containment inoperability constitutes a condition reportable under 10CFR50.72(b)(3)(v)(C) and (D). The NRC Senior Resident Inspector has been informed. |
| ENS 55715 | 27 January 2022 15:07:00 | Cooper | NRC Region 4 | GE-4 | The Licensee provided the following information via email: On January 27, 2022 at 1038 CST, with Cooper Nuclear Station in Mode 1, 100 percent power, the meteorological tower primary and backup data acquisition system failed, which resulted in a loss of meteorological data to the plant. Information technology personnel investigated and restored the primary system to service. Meteorological data to the plant was restored at 1105 CST on January 27, 2022. This notification Is being made due to a loss of emergency assessment capability In accordance with 10 CFR 50.72(b)(3)(xiii). The NRC Resident Inspector has been Informed. |
| ENS 55703 | 13 January 2022 12:03:00 | Cooper | NRC Region 4 | GE-4 | The following information was provided by the licensee via fax: On 1/13/2022 at 0806 CST, Nebraska Public Power District was notified by Atchison County Missouri of a spurious actuation of (Cooper Nuclear Station) (CNS) Emergency Siren 2113 near Rockport, Missouri from approximately 0800 to 0805 CST. Nebraska Public Power District will issue a press release for this event. The CNS Emergency Alert System (EAS) was not activated. This condition is reportable under 10 CFR 50.72(b)(2)(xi) for any event or situation for which a news release is planned or notification to other government agencies has been or will be made which is related to heightened public or government concern. The NRC Senior Resident Inspector has been informed. |
| ENS 55614 | 29 November 2021 18:47:00 | Arkansas Nuclear | NRC Region 4 | B&W-L-LP | On November 29, 2021 at 1458 CST, Arkansas Nuclear One, Unit 1, (ANO-1) automatically tripped due to high Reactor Coolant System pressure after the 'A' Main Feedwater Pump was manually tripped due to lowering speed. ANO-1 is currently stable in MODE 3 (Hot Standby) maintaining pressure and temperature with the P-75 Auxiliary Feedwater pump and steaming to the Condenser. There are no indications of a radiological release on either unit as a result of this event. This report satisfies the reporting criteria of 10 CFR 50.72(b)(2)(iv)(B) and 10 CFR 50.72(b)(3)(iv)(A) for the Reactor Protection System actuation. The NRC Senior Resident Inspector has been notified. Unit 2 was not affected. |
| ENS 55561 | 4 November 2021 09:12:00 | Grand Gulf | NRC Region 4 | GE-6 | A non-licensed employee had a confirmed positive for alcohol during a random fitness-for-duty test. The employee's access to the plant has been terminated. The NRC Resident Inspector has been notified. |
| ENS 55506 | 4 October 2021 19:59:00 | Arkansas Nuclear | NRC Region 4 | CE | At 1433 CDT, on October 4, 2021, Arkansas Nuclear One, Unit 2 (ANO-2) completed the analysis related to an indication revealed on head penetration 46 during Reactor Vessel Closure Head inspections. It was determined the indication is not acceptable under ASME code requirements. The indication displays characteristics consistent with primary water stress corrosion cracking. No leak path signal was identified during ultrasonic testing. The plant was in cold shutdown at 0 percent power and in Mode 6 for a refueling outage at the time of discovery. Repair actions will be completed prior to plant startup from the outage. This condition has no impact to the health and safety of the public. This report is being made in accordance with 10 CFR 50.72(b)(3)(ii)(A) for degradation of a principal safety barrier. This is the only indication that is currently present, however, if additional indications are found, they will also be repaired prior to the plant startup. The NRC Senior Resident Inspector has been notified. |
| ENS 55451 | 9 September 2021 04:19:00 | Grand Gulf | NRC Region 4 | GE-6 | At 0033 CDT on September 9, 2021, Grand Gulf Nuclear Station (GGNS) was operating at 70 percent power when the High Pressure Core Spray (HPCS) was declared inoperable. The inoperability determination was made due to control room annunciations. In accordance with GGNS Technical Specification 3.5.1.B.1, the Reactor Core Isolation Cooling system was verified to be operable. Troubleshooting is in progress. This event is being reported in accordance with 10 CFR 50.72(b)(3)(v)(D) as an event or condition which could have prevented the fulfillment of a safety function. The NRC Resident Inspector has been notified. |