Semantic search
| Discovered date | Reporting criterion | Title | Description | LER | |
|---|---|---|---|---|---|
| ENS 56815 | 6 July 2022 04:00:00 | 10 CFR 20.2201(a)(1)(ii) | Lost Sealed Sources | The following information was provided by the licensee via phone and email: This is a non-emergency 30-day notification for missing licensed material. This event is reportable in accordance with 10 CFR 20.2201(a)(1)(ii). On September 25, 2023, while performing the required semi-annual source leak check and inventory, radiation protection personnel could not locate seven sealed radioactive sources. Five of the sources exceed the reporting threshold of ten times the activity listed in 10 CFR 20 Appendix C. Of the five sources, four were Ni-63 sources previously utilized in security bomb detection equipment with a current source radioactivity of between 7.1 and 8.7 mCi. The fifth sealed source exceeding the reporting threshold is an Am-241 former lab calibration standard with a source radioactivity of 0.97 microcuries. These sources were last accounted for on July 6, 2022. Pilgrim's accountability process does not require leak checks or physical inventory of sources that are out of service. A search was conducted for the missing sources; however, they could not be located. These sealed sources are classified as Category 5 radioactive sources in accordance with the International Atomic Energy Agency (IAEA) Safety Guide No. RS-G-1.9. Sources that are less than Category 3 (Cat 4 and 5 sources) are very unlikely to cause permanent injury to individuals. Based on the activity of Ni-63 and Am-241 present in the sources, this 30-day phone notification to NRC is provided pursuant to 10CFR20.2201(a)(1)(ii). The required written report pursuant to 10CFR20.2201(b)(1) will be provided to NRC within 30 days. The Resident Inspector has been notified. The licensee will notify State and local authorities. THIS MATERIAL EVENT CONTAINS A 'Less than Cat 3' LEVEL OF RADIOACTIVE MATERIAL Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf | |
| ENS 55844 | 15 April 2022 14:00:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Notification of Environmental Report to Another Government Agency | The following information was provided by the licensee via email: On April 15, 2022 at 1000 hours (EDT), four off-site notifications were made to the Commonwealth of Massachusetts Department of Environmental ÿProtection (MADEP) in accordance with the Massachusetts Contingency Plan (310 CMR 40.0000). ÿThe notifications document non-radiological contaminants found slightly above reportable concentrations in select soil and groundwater samples collected during site characterization efforts, as part of the decommissioning process, from four parcels of land at the property.ÿ ÿReportable concentrations in soil were identified in a composite sample for Polychlorinated Biphenyls (PCBs). ÿReportable concentrations in groundwater were identified in samples for per- and polyfluoroalkyl substances (PFAS) and Semi Volatile Organic Compound (SVOC). Additionally, the reports include sample results where laboratory reporting limits equaled or exceeded reporting thresholds. This notification is being made solely as a four-hour, non-emergency notification for a Notification of Other Government Agency in accordance with 10 CFR 50.72(b)(2)(xi).ÿ There was no impact on the health and safety of the public or plant personnel. The NRC Lead Decommissioning Inspector and NMSS Project Manager assigned to Pilgrim have been notified. | |
| ENS 55567 | 9 November 2021 15:40:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification Due to Violation of Discharge Permit | At 1040 hours EST, November 9, 2021, the site reported a violation of the station National Pollutant Discharge Elimination System permit. The 24-hour environmental report addressed an unauthorized discharge of 7,245 gallons of non-radiological water that was pumped into a storm drain to de-water an on-site electrical vault located outside of the protected area. This discharge occurred from 0800 to 1230 hours on November 8, 2021. Sampling and analysis of the vault water is in progress to assess for the presence of pollutants. This notification is being made solely as a four-hour, non-emergency notification for a Notification of Other Government Agency. This event is reportable in accordance with 10 CFR 50.72(b)(2)(xi). There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. The licensee notified the U.S. Environmental Protection Agency and the Commonwealth of Massachusetts Department of Environmental Protection. | |
| ENS 55202 | 21 April 2021 11:52:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification to the Commonwealth of Massachusetts | On April 21, 2021, at 0752 hours (EDT), an offsite notification was made to the Commonwealth of Massachusetts Department of Environmental Protection (MADEP) in accordance with Regulation 310 CMR 40.0000: Massachusetts Contingency Plan (MCP). The notification documents non-radiological contaminants found above reportable concentrations in select samples collected during site characterization efforts. The reported reportable concentrations were slightly above reporting limits in a soil sample for Per and Polyfluoroalkyl Substances (PFAS), two groundwater sampling locations for PFAS, and isolated instances of metals in groundwater including Arsenic, Vanadium, Lead, Antimony, Beryllium, Cadmium, Chromium, Nickel, and Thallium. This report is being submitted in accordance with 10CFR50.72(b)(2)(xi) based on notification being made to another government agency. Concentrations above reporting limits have been entered into the site's corrective action program. As per MCP, the site will proceed with requirements to implement the phased MCP process. This condition does not represent a threat to station personnel or to members of the general public. | |
| ENS 55071 | 18 January 2021 21:00:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification Due to Leak from Underground Sewage Storage Tank | On January 18, 2021 at 1600 hours (EDT), Holtec Decommissioning International (HDI) made an off-site notification to the Environmental Protection Agency's Enforcement and Compliance Assurance Division in accordance with Section B of the station's National Pollutant Discharge Elimination System (NPDES) Permit No. 0003557. The event was associated with an underground sewage water system holding tank. The specific details of the occurrence are as follows: On January 13, 2021 at 1000 hours (EDT) site personnel identified what appeared to be water bubbling up from an unidentified cover within the security protected area of the site. The water emanating from the cap had no visible color or solid material and no odor. The water estimated at 25 gallons per hour or less was flowing to a site storm drain connected to permitted outfall number 007. Initial indication was that the water was potable water as part of the station's fire protection system. Further investigation determined that a back-up in an underground sewage holding tank inlet was the source of the leakage. By 1400 hours (EDT) when bathrooms including toilets on site were shutdown and removed from service, efforts were underway to pump the tank and remove the blockage, and the bubbling from the cover had stopped. The licensee has notified the Massachusetts Environmental Protection Agency, the Massachusetts Emergency Management Agency and the NRC Resident Inspector. | |
| ENS 54895 | 10 September 2020 14:02:00 | 10 CFR 26.719, FFD Reporting requirements | Fitness for Duty (Ffd) Policy Violation | A contract employee supervisor had a confirmed positive for alcohol during a random fitness-for-duty test. The employee's rights to access the plant have been suspended. The licensee notified the NRC Region I Decommissioning Lead Inspector. | |
| ENS 54071 | 18 May 2019 03:03:00 | 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation 10 CFR 50.72(b)(3)(iv)(A), System Actuation | Manual Reactor Scram Due to Degrading Condenser Vacuum | On Friday, May 17, 2019 at 2303 (EDT), with the reactor at 70 (percent) core thermal power, Pilgrim Nuclear Power Station initiated a manual reactor scram due to degrading condenser vacuum as a result of the trip of Seawater Pump B. All control rods inserted as designed. The plant is in hot shutdown. Plant safety systems responded as designed. Pressure is being controlled using the Mechanical Hydraulic Control System and Main Condenser. Reactor water level is being maintained with the feedwater and condensate system. During the manual reactor scram, the plant experienced the following isolation signals as designed: "Group 2 Isolation: Miscellaneous containment isolation valves Group 6 Isolation: Reactor Water Clean-up Reactor Building Isolation Actuation Due to the Reactor Protection System actuation while critical, this event is being reported as a four-hour, non-emergency notification in accordance with 10 CFR 50.72(b)(2)(iv)(B), 'any event that results in actuation of the reactor protection system (RPS) when the reactor is critical...' This notification is also being made in accordance with 10 CFR 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...' (B)(2) 'General containment isolation signals affecting containment isolation valves in more than one system or multiple main steam isolation valves (MSIVs).' This event has no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. The licensee will notify the Massachusetts Emergency Management Agency. | |
| ENS 53818 | 8 January 2019 05:00:00 | 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | Reactor Core Isolation Cooling Declared Inoperable | On January 8, 2019, at 0945 EST Pilgrim Nuclear Power Station discovered that the Reactor Core Isolation Cooling (RCIC) system failed to meet its surveillance test requirements and was declared inoperable; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v), 'event or condition that could have prevented the fulfillment of a safety function: (D), mitigate the consequences of an accident.' There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. | |
| ENS 53815 | 5 January 2019 15:40:00 | 10 CFR 50.72(b)(3)(v)(A), Loss of Safety Function - Shutdown the Reactor | En Revision Imported Date 2/12/2019 | EN Revision Text: POTENTIAL LOSS OF MSIV SCRAM FUNCTION DURING MAIN STEAM LINE ISOLATION VALVE TESTING At approximately 1040 EST on January 5, 2019, during evaluation of test results for the 'C' Main Steam Isolation Valve (MSIV), it was determined that closure of three of four Main Steam Lines would not necessarily have resulted in a full scram during testing due to failure of a limit switch (LS-6) associated with MSIV-1C while in the test configuration. This condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v), 'Any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to: (A) Shut down the reactor and maintain it in a safe shutdown condition.' The system was restored from the testing configuration at 1057 EST and the failed trip channel was placed in the tripped condition at 1326 EST thus restoring the design function. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
The purpose of the notification is to retract ENS Notification 53815 made on 01/05/19 for Pilgrim Nuclear Power Station. The previous notification reported that there was a potential loss of Main Steam Isolation Valve (MSIV) scram function during main steam line isolation valve testing, at the time of discovery, due to failure of a limit switch (LS-6) associated with MSIV-1C while in the test configuration. Subsequent evaluation has demonstrated that the scram function credited in the design basis was not lost. Specifically, after an Engineering Evaluation, it has been determined that the MSIV position RPS logic was not lost for those functions within the design basis and, as such, was capable of performing its intended safety function. The NRC Resident Inspector has been notified. Notified the R1DO (Cahill). | |
| ENS 53648 | 5 October 2018 04:00:00 | 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation 10 CFR 50.72(b)(3)(iv)(A), System Actuation | Automatic Reactor Scram Due to Low Reactor Water Level | On Friday, October 5, 2018 at 1209 hours, with the reactor at 100 percent core thermal power, Pilgrim Nuclear Power Station (PNPS) automatically tripped due to reactor water level perturbation and receipt of a low reactor water level Reactor Protection System (RPS) signal. The cause of the low reactor water level is under investigation. The plant is in hot shutdown. All other plant systems responded as designed. Pressure is being controlled using the Mechanical Hydraulic Control System and Main Condenser. Reactor water level is being maintained with the feedwater and condensate system. During the automatic reactor scram the plant experienced the following isolation signals as designed: Group 2 Isolation: Miscellaneous containment isolation valves Group 6 Isolation: Reactor Water Clean-up Reactor Building Isolation System Actuation Due to the RPS actuation while critical, this event is being reported as a four-hour, non-emergency notification in accordance with 10 CFR 50.72(b)(2)(iv)(B), 'any event that results in actuation of the reactor protection system (RPS) when the reactor is critical.' This notification is also being made in accordance with 10 CFR 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 ... ' (B)(2) 'General containment isolation signals affecting containment isolation valves in more than one system.' This event has no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. The licensee will notify the Massachusetts Emergency Management Agency. | |
| ENS 53287 | 25 March 2018 20:16:00 | 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded | Control Rod Drive Piping Potentially Inoperable | On March 25, 2018 at 1616 hours (EDT), with the reactor in cold shutdown condition, two control rod drive piping lines were determined to be potentially inoperable in the event of a design basis earthquake due to support defects. The control rod drive piping forms a portion of the reactor coolant pressure boundary and primary containment boundary. The supports will be repaired prior to plant startup. This event had no impact on the health and/or safety of the public. The NRC Resident Inspector has been notified. The licensee will notify the Commonwealth of Massachusetts.
The purpose of the notification is to retract ENS notification 53287 made on 03/25/18 for Pilgrim Nuclear Power Station. The previous notification reported that control rod drive (CRD) piping could be potentially inoperable in the event of a design basis earthquake, at the time of discovery, due to piping support defects. Subsequent evaluation has demonstrated that the piping was not inoperable. Specifically, after an engineering evaluation, it has been determined that the CRD Hydraulic System operability was never lost and the system was operable, although non-conforming, based on the support configuration not conforming to the pipe support drawings. The affected pipe supports have been restored or reworked to the proper design condition in accordance with the design drawings. The CRD System has subsequently been restored to a fully operable status. Notified R1DO (Jackson) and IRD MOC (Pham). | |
| ENS 53259 | 13 March 2018 14:00:00 | 10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat | Off-Site Power Unavailable Due to Winter Storm | On March 13, 2018 at 1000 hours (EDT), with the reactor in Cold Shutdown condition, both 345kV incoming power lines and 23 kV Shutdown Transformer became unavailable during the Northeast winter storm. Per procedures, the emergency on-site emergency power supplies (Emergency Diesel Generators) were running and providing power to essential systems. In addition, the back-up Diesel Air Compressor was in service and one Reactor Protection System bus was on the back-up power supply prior to the loss. With both 345kV incoming power lines and 23 kV Shutdown Transformer unavailable, Pilgrim Nuclear Power Station procedures direct a report be made to the NRC per the requirements of Title 10 Code of Federal Regulations 50.72(b)(3)(v), any event that could have prevented the fulfillment of the safety function. No actual loss of safety function has occurred since the on-site emergency power supplies are maintaining the reactor in a safe shutdown condition and removing residual heat. The loss of incoming power is under investigation. This event had no impact on the health and/or safety of the public. The NRC Resident Inspector has been notified. | |
| ENS 53242 | 3 March 2018 04:15:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Potential Loss of Offsite Response Capabilities | At 2315 EST on March 2, 2018, Pilgrim Nuclear Power Station (PNPS) determined, based on information received from the Commonwealth of Massachusetts, that there may be a potential loss of offsite response capabilities due to ongoing severe natural hazard conditions (i.e., major winter storm) along the coast of Massachusetts. According to information received by PNPS, towns within the 10 Mile EP Radius could be hampered in implementing some protective actions specified in the emergency plan in the unlikely event an emergency were to occur. There is no condition at the Station that would warrant implementation of any emergency plan at this time. PNPS continues to operate safely and is monitoring the weather conditions closely. The Station maintains emergency assessment, response, and communication capability. This report is being made conservatively in accordance with 10 CFR 50.72(b)(3)(xiii) which is any event that results in a major loss of emergency assessment capability, offsite response capability, or offsite communications capability. As stated previously, the Station maintains emergency assessment, response, and communication capability. The licensee notified the NRC Resident Inspector. | |
| ENS 53147 | 4 January 2018 19:10:00 | 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation 10 CFR 50.72(b)(3)(iv)(A), System Actuation | Manual Reactor Scram Due to Partial Loss of Offsite Power During Winter Storm | On January 4, 2018, at 1410 hours EST, with the reactor at approximately 100 percent power and steady state conditions, the winter storm across the Northeast caused the loss of offsite 345 kV Line 342. Reactor power was reduced to approximately 81 percent and a procedurally required manual reactor scram was initiated. All control rods fully inserted. As a result of the reactor scram, indicated reactor water level decreased, as expected, to less than +12 inches resulting in automatic actuation of the Primary Containment Isolation Systems for Group II - Primary Containment Isolation and Reactor Building Isolation System, and Group VI - Reactor Water Cleanup System. Reactor Water Level was restored to the normal operating band. The Primary Containment Isolation Systems have been reset. The Reactor Protection System signal has been reset. Following the reactor scram, the non-safety related Control Rod Drive Pump "B" tripped on low suction pressure. Control Rod Drive Pump "A" was placed in service. All other systems operated as expected, in accordance with design. This event is reportable per the requirements of Title 10, Code of Federal Regulations (CFR) 50.72 (b)(2)(iv)(B) - "RPS Actuation" and 10 CFR 50.72 (b)(3)(iv)(A) - "Specified System Actuation. This event had no impact on the health and/or safety of the public. The NRC Resident Inspector has been notified. The main steam isolation valves are open with decay heat being removed via steam to the main condenser. Offsite power is still available from 345kV line 355. As a contingency, emergency diesel generators are running and powering safety busses per licensee procedure. The licensee notified the Commonwealth of Massachusetts. The licensee will be notifying the town of Plymouth as part of their local notifications. The licensee will be issuing a press release. | |
| ENS 53041 | 30 October 2017 06:47:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Severe Weather Causes Loss of Power to Support Buildings | There was a loss of power from the local grid which did not affect the power block. The support buildings lost power and a UPS failed which affects computers, switching, and telephones. This includes a loss of the Emergency Response Data System (ERDS). The Joint Information Center and Emergency Operations Facility were not affected. Though this is a major loss of communications ability, alternate communications methods are available. The licensee notified the NRC Resident Inspector. | |
| ENS 52820 | 20 June 2017 18:44:00 | 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Secondary Containment Declared Inoperable Due to Both Airlock Doors Open Simultaneously | On June 20, 2017, at 1444 hours (EDT), with the reactor at 100% core thermal power and steady state conditions, plant personnel identified that both doors in one of the secondary containment airlocks (Door #58 and Door #85) were open briefly as part of normal passage of personnel. The Technical Specification definition of SECONDARY CONTAINMENT INTEGRITY states 'At least one door in each access opening is closed.' Actions were taken to immediately close both doors and restore operability of secondary containment. PNPS (Pilgrim Nuclear Power Station) is providing an 8-hour non-emergency notification in accordance with 10 CFR 50.72(b)(3)(v)(C), an event or condition that could have prevented fulfillment of a safety function needed to control the release of radioactive material. The NRC Resident Inspector has been notified. The licensee notified the Commonwealth of Massachusetts. | |
| ENS 52744 | 10 May 2017 18:11:00 | 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded | Appendix J Local Leakage Exceeded Acceptance Criteria | On Wednesday May 10, 2017, at 1411 EDT, with the reactor at 0 percent core thermal power (CTP), Pilgrim Nuclear Power Station (PNPS) was in a Refueling Outage, performing a review of Local Leak Rate Testing results, when it was concluded that PNPS had exceeded its Title 10 Code of Federal Regulations Part 50, Appendix J, Option B, Type B and C Local Leak Rate Test (LLRT) leakage criteria. Previously, on April 22, 2017, when PNPS was performing LLRT of the High Pressure Coolant Injection (HPCI) steam exhaust line check valves, both valves failed to meet their LLRT acceptance criteria specified in plant procedures. Neither of the check valves seated acceptably. Based on the ongoing evaluation of these test exceedances, it was concluded that these test results cause the plant to exceed the overall as-found minimum path Appendix J acceptance criteria of 0.6 La (126.3 SLM (Standard Liters per Minute)). Further investigation is ongoing. This event has no impact on the health and safety of the public. The licensee has notified the NRC Senior Resident Inspector. This notification is being made in accordance with 10 CFR 50.72(b)(3)(ii)(A), any event or condition that resulted in the condition of the nuclear power plant, including its principle safety barriers, being seriously degraded. The licensee will notify the Commonwealth of Massachusetts Emergency Management Agency. | |
| ENS 52655 | 31 March 2017 15:55:00 | 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | Pressure Suppression Pool Declared Inoperable Due to Torus High Water Level | On March 31, 2017 at 1155 hours (EDT), with the reactor at 97% core thermal power and steady state conditions, operators inadvertently caused water level to rise in the Pressure Suppression Pool (TORUS). Pilgrim Nuclear Power Station (PNPS) was restoring normal system valve line-ups after performing flushing of the suction piping of the Core Spray system in accordance with station procedures. During the process of restoring the appropriate valve line-ups, water was inadvertently transferred to the TORUS from the Condensate Storage Tank. The cause of the event is understood. The Technical Specification (TS) Limiting Condition for Operation (LCO) Action Statement (AS) 3.7.A.5 was entered. The LCO AS was exited at 1540 when TORUS water level was restored to the limits specified in LCO's 3.7.A.1.b and 3.7.A.1.m. Because the TORUS was declared inoperable, PNPS is providing an 8-hour non-emergency notification in accordance with 10 CFR 50.72(b)(3)(v)(D), an event or condition that could have prevented fulfillment of a safety function needed to mitigate the consequences of an accident. This was a case of the water level in the TORUS being above the TS limit. The TORUS was potentially available to provide cooling to the reactor if required. The NRC Resident Inspector has been notified. The licensee notified the Commonwealth of Massachusetts and Plymouth County. | |
| ENS 52643 | 27 March 2017 22:25:00 | 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | Hpci Declared Inoperable Due to Inadvertent Isolation | On March 27, 2017, at 1825 hours EDT, with the reactor at 100 percent core thermal power and steady state conditions, technicians inadvertently caused a High Pressure Coolant Injection (HPCI) System isolation, by testing the incorrect temperature switches in the TIP (Traversing In-core Probe) room. Pilgrim Nuclear Power Station (PNPS) was performing testing on the temperature switches for Reactor Core Isolation Cooling (RCIC), but the HPCI temperature switches were inadvertently actuated causing HPCI to isolate. The Limiting Condition for Operation (LCO) Action Statement 3.5.c.2 has been entered and the planned testing has been secured pending further investigation. PNPS is providing an 8-hour non-emergency notification that the HPCI System was declared inoperable in accordance with 10 CFR 50.72(b)(3)(v)(D), an event or condition that could have prevented fulfillment of a safety function needed to mitigate the consequences of an accident. HPCI was returned to Operable within 40 minutes. The licensee notified the NRC Resident Inspector and the Commonwealth of Massachusetts. | |
| ENS 52492 | 16 January 2017 16:55:00 | 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Failure of Reactor Building Isolation Dampers to Isolate | On January 16, 2017, with the reactor at 100 percent and the mode switch in RUN, Pilgrim Station was performing preventative maintenance of secondary containment isolation dampers when dampers AO-N-82 and AO-N-83, refueling floor supply isolation dampers, failed to fully close when the control switches were taken to close. This 8-hour non-emergency notification is being made in accordance with 10 CFR 50.72(b)(3)(v), Any event or condition that at the time discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to: (C) Control the release of radioactive material; or (D) Mitigate the consequences of an accident. The reactor building isolation dampers were cleaned and lubricated and post-work tested and timed in accordance with station procedures to verify that they had satisfactory closing times. Pilgrim Nuclear Power Station has returned the dampers to Operable status. The licensee will notify the Commonwealth of Massachusetts. The licensee has notified the NRC Resident Inspector. | |
| ENS 52449 | 20 December 2016 23:30:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification - Release of Hydrogen Gas in Excess of the Reportable Quantity of Ten Pounds | At 1830 EST on 20 December, 2016 the Massachusetts Department of Environmental Protection and the Plymouth Massachusetts Fire Department were notified of a Hydrogen release in accordance with plant procedures and 310CMR40.300, Massachusetts Contingency Plan Notification for Oil and Hazardous Material; Identification and Listing of Oil and Hazardous Material, due to a release of hydrogen gas to the environment exceeding the reportable quantity of ten pounds. The release, which is an expected part of a routine plant start-up was from the generator hydrogen cooling system. This event posed no danger to the health and safety of plant personnel or members of the general public. The NRC Resident Inspector has been notified. | |
| ENS 52352 | 7 November 2016 21:09:00 | 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | Hpci Declared Inoperable Due to Failure of Ist Surveillance Test | On November 7, 2016, at 1609 (EST), with the reactor at 100 percent core thermal power and steady state conditions, the High Pressure Coolant Injection (HPCI) system was declared inoperable. Pilgrim Nuclear Power Station (PNPS) was performing planned quarterly testing per Technical Specifications 4.13.A.1. During a review of the HPCI pump data taken during the test, it was determined that the recorded vibration reading on the Main Pump Outboard horizontal point (P4H) was 0.8335 in./sec which exceeds the IST required action range high limit of less than or equal to 0.830 in./sec. Accordingly, the HPCI pump was declared inoperable. The Limiting Condition for Operation Action Statement 3.5.C.2 has been entered and planned troubleshooting Into the cause of the high vibration is in progress. In accordance with 10 CFR 50.72(b)(3)(v)(D), PNPS is providing an 8-hour non-emergency notification that the HPCI System is inoperable. This event had no impact on the health and/or safety of the public. The NRC Resident Inspector has been notified. The licensee will be notifying the State of Massachusetts regarding the event. | |
| ENS 52231 | 9 September 2016 21:39:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification - Release of Hydrogen Gas in Excess of the Reportable Quantity of Ten Pounds | At 1739 (EDT) on Friday September 9, 2016 the Massachusetts Department of Environmental Protection and the Plymouth Massachusetts Fire Department were notified of a Hydrogen release in accordance with plant procedures and 310CMR40.300, Massachusetts Contingency Plan Notification for Oil and Hazardous Material; Identification and Listing of Oil and Hazardous Material, due to a release of hydrogen gas to the environment exceeding the reportable quantity of ten pounds. The Massachusetts DEP Tracking Number is RTN4-26311. The release was from the generator hydrogen cooling system. There was no plant damage. Hydrogen system pressure has been restored to the normal operating band with the Main Generator secured and is stable. The cause of the event is under investigation. This event posed no danger to the health and safety of plant personnel or members of the general public. The NRC Resident Inspector has been notified.
The Plymouth Massachusetts Fire Department was notified on Monday, September 12, 2016, at 1411 EDT. This clarifies information applicable to the local notification as identified in the original notification. Notified R1DO(Noggle) and NSIR (Stapleton) via email. | |
| ENS 52223 | 6 September 2016 12:27:00 | 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation 10 CFR 50.72(b)(3)(iv)(A), System Actuation | Manual Reactor Scram Due to High Reactor Water Level | On Tuesday, September 6, 2016 at 0827 (EDT), with the reactor at 91% core thermal power (CTP), Pilgrim Nuclear Power Station (PNPS) operators initiated a manual reactor scram due to high reactor water level resulting from feedwater level control oscillation. Other than the feedwater level control oscillations, all other plant systems responded as designed. Plant cooldown is in progress using the High Pressure Coolant Injection System in the pressure control mode. The plant is in hot shutdown. The cause of the feed water level control oscillations is under investigation. This event has no impact on the health and safety of the public. Subsequent to the manual reactor scram the plant experienced the following isolation signals: Group 1 Isolation: Main Steam Isolation Valves Group 2 Isolation: Miscellaneous containment isolation valves Group 6 Isolation: Reactor Water Clean-up Reactor Building (Ventilation) Isolation Actuation The licensee has notified the NRC Senior Resident Inspector. This notification is being made in accordance with 10 CFR 50.72(b)(2)(iv)(B), 'any event that results in actuation of the reactor protection system (RPS) when the reactor is critical...'. This notification is also being made in accordance with 10 CFR 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...' (B)(2) 'General containment isolation signals affecting containment isolation valves in more than one system or multiple main steam isolation valves (MSIVs).' All rods were inserted. The plant is stable with normal off-site power line-up. The licensee will notify the Commonwealth of Massachusetts. | |
| ENS 52181 | 15 August 2016 19:52:00 | 10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | Salt Service Water System Declared Inoperable | On Monday, August 15, 2016 at 1552 (EDT), with the reactor at (about) 70 percent core thermal power (CTP), Pilgrim Nuclear Power Station (PNPS) entered a 24-hour shutdown Limiting Condition for Operation Action Statement (LCO-AS) for Salt Service Water (SSW) inlet temperature exceeding the Technical Specification (TS) limit in TS 3.5.B.4. The LCO-AS was subsequently exited at 1651 hours when the temperature of SSW trended to below the TS limit. Under certain design conditions, the SSW system is required to provide cooling water to various heat exchangers such as the Reactor Building Closed Cooling Water (RBCCW) and Turbine Building Closed Cooling Water (TBCCW) systems. When the inlet temperature to these supplied loads exceeds the 75 degrees F limit established in the TS, the SSW system is conservatively declared inoperable until the temperature trends below this value. This condition existed for approximately 60 minutes. The SSW temperature is being closely monitored and trended on a continuous basis. This event has no impact on the health and safety of the public. The licensee has notified the NRC Senior Resident Inspector. This notification is being made in accordance with 10 CFR 50.72(b)(3)(v)(B) and 10 CFR 50.72(b)(3)(v)(D) due to an event or condition that could have prevented fulfillment of a safety function. The licensee will be notifying the Commonwealth of Massachusetts Emergency Management Agency. | |
| ENS 52056 | 30 June 2016 18:30:00 | 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Both Primary Containment Isolation Valves for a Penetration Potentially Inoperable | On June 30, 2016 at 1430 (EDT), with the reactor at 100 (percent) and the mode switch in RUN, Pilgrim Station determined both Primary Containment Isolation Valves (PCIVs) CV-5065-91 and CV-5065-92 for Drywell Penetration X-32A were inoperable due to the potential failure of relays relied on to perform the primary containment isolation function. The valves have been closed and deactivated in the isolated condition in accordance with Technical Specification Limiting Condition For Operation Action Statement 3.7.A.2.b. Preparations are in progress to replace the relays to restore the valves to operable status. This 8-hour notification is being made in accordance with 10 CFR 50.72 (b)(3)(v)(C) and 10 CFR 50.72 (b)(3)(v)(D). The licensee has notified the NRC Senior Resident Inspector. The licensee will notify the Commonwealth of Massachusetts.
This notification is being made to retract event notification EN 52056 made by Pilgrim Nuclear Power Station on June 30, 2016, that reported the potential failure of relays that could have prevented the fulfillment of the safety function of primary containment isolation valves (PCIVs) needed to control the release of radioactive material and mitigate the consequences of an accident. Post replacement testing of the removed relays associated with PCIV CV-5065-91 and CV-5065-92 demonstrated the ability of these relays to perform the required safety function. Based on the test results, no loss of PCIS safety function occurred while the relays were physically installed and operating. Therefore, Event Number 52056, made on June 30, 2016, is being retracted. The NRC Senior Resident Inspector has been notified. Notified R1DO (Powell). | |
| ENS 51924 | 12 May 2016 20:47:00 | 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | Deterioration of Spent Fuel Pool Rack Neutron Absorbing Material | On May 12, 2016, at 16:47 EDT with the reactor at 100% power and the mode switch in RUN, an assessment of the Spent Fuel Pool racks containing neutron absorbing material concluded that some degradation had occurred. The result is that we cannot assure we are maintaining Keff < 0.95 as required per design. Conservative measures have been implemented to ensure public health and safety. Recent planned testing conducted in the spent fuel pool determined that one rack panel had degradation of the neutron absorbing material in excess of what had been analyzed. An extent of condition review indicated additional potential at-risk locations may exist. Analyses are being performed to determine the potential impact and mitigating actions. Fuel pool conditions are safe and stable. Conservative measures have been implemented and spent fuel safety is maintained. Based on the above, the condition is reportable to the NRC as an Unanalyzed Condition under 10 CFR 50.72(b)(3)(ii), and requires an 8 hour notification. The condition is also reportable in accordance with 10 CFR 50.73 (a)(2)(ii). The licensee has notified the NRC Senior Resident Inspector. The licensee will notify the Commonwealth of Massachusetts. | 05000293/LER-2016-003 |
| ENS 51862 | 12 April 2016 04:50:00 | 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | Loss of Both Emergency Diesel Generators | On April 12, 2016, with the reactor at 100 percent power and the mode switch in RUN, Pilgrim Nuclear Power Station entered an unplanned 24-hour Limiting Condition for Operation (LCO) action statement due to both emergency diesel generators (EDG) being inoperable (Technical Specification 3.5.F.1). At 0050 (EDT) this morning, with EDG B out of service for a planned LCO maintenance window, EDG A was declared inoperable due to a 130 drop per minute leak on a line to a jacket water pressure indicator. Repairs to EDG A are underway at this time. The following plant equipment has been verified operable: both 345 Kv transmission lines; 23kV transmission line; Station Blackout EDG. This condition is reportable to the NRC Staff as an Event or Condition that Could Have prevented Fulfillment of a Safety Function (Mitigate the consequences of an accident) under 10 CFR 50.72(b)(3)(v)(D), and requires an 8-hour notification. The licensee has notified the NRC Senior Resident Inspector. The licensee will notify the Commonwealth of Massachusetts. | |
| ENS 51523 | 9 November 2015 13:00:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Technical Support Center Unavailable Due to Planned Maintenance | On Monday, November 9, 2015 at 0800 (EST), planned routine maintenance was initiated on the Technical Support Center/Operations Support Center (TSC/OSC) ventilation system. The planned maintenance is to replace the charcoal filters and test the HVAC trains. All other TSC/OSC functions remain available. Under certain accident conditions the TSC/OSC may become unavailable as a result of the ventilation system not being available. Existing Emergency Procedures direct the responsible Emergency Plant Manager to relocate the TSC/OSC staff to the designated alternate location. The affected Emergency Response Organization facility leads have been informed. The licensee has notified the NRC Senior Resident Inspector. The Commonwealth of Massachusetts will be notified. This notification to the USNRC Operations Center is being made in accordance with 10 CFR 50.72(b)(3)(xiii) due to the potential loss of an Emergency Response Facility (ERF).
At 1730 EST on Monday, November 9, 2015, the TSC/OSC ventilation system was restored to service. The licensee will notify the NRC Resident Inspector. Notified R1DO (Arner). | |
| ENS 51456 | 5 October 2015 21:25:00 | 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | Safe Shutdown Analysis for Fire Event - Open Item with Potential to Impact Capability to Operate Motor Operated Valves | At 1725 (EDT) on Monday, October 5, 2015, while updating the site fire safe shutdown analysis report, Pilgrim Nuclear Power Station (PNPS) identified vulnerabilities in two (2) specific fire areas that required a compensatory fire watch. The compensatory fire watches have already been established. The specific concern involves the unlikely scenario that fire forces evacuation of the control room. In addition, it is postulated that motor operated valves cannot be operated from their alternate control location due to spurious operation caused by hot shorts in control wiring. The specific failure mode is described in NRC Information Notice (IN) 92-18. Engineering modifications are under development and scheduled for implementation to address this specific IN 92-18 concern. Based on the above, the condition is reportable to the NRC as an unanalyzed condition that significantly degrades plant safety. As such the condition is reportable under 50.72(b)(3)(ii)(B), and requires an 8 hour notification. The licensee has notified the NRC Resident Inspector. | |
| ENS 51338 | 22 August 2015 20:28:00 | 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation 10 CFR 50.72(b)(3)(iv)(A), System Actuation | Reactor Scram Due to a Single Msiv Closure | On Saturday, August 22, 2015, at 1628 (EDT), with the reactor at 100% core thermal power (CTP) the Pilgrim Nuclear Power Station (PNPS) experienced an automatic reactor scram signal due to the rapid closure of one main steam isolation valve (MSIV). Other than the MSIV all other plant systems responded as designed. Plant cooldown is in progress using steam bypass to the main condenser. The plant is in hot shutdown. The cause of the MSIV closure is still under investigation. This event has no impact on the health and safety of the public. The licensee has notified the NRC Senior Resident Inspector. This notification is being made in accordance with 10 CFR 50.72(b)(2)(iv)(B), 'Any event that results in actuation of the reactor protection system (RPS) when the reactor is critical'. Subsequent to the reactor scram the plant experienced the following isolation signals: - Group 2 Isolation: Miscellaneous containment isolation valves
- Group 6 Isolation: Reactor Water Clean-up
- Reactor Building Isolation Actuation
This notification is also being made in accordance with 10 CFR 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' (B)(2) 'General containment isolation signals affecting containment isolation valves in more than one system or multiple main steam isolation valves (MSIVs).' Plant response was considered normal and the plant is in a stable shutdown / cooldown condition. The license will be notifying the Commonwealth of Massachusetts. | |
| ENS 51301 | 9 August 2015 20:27:00 | 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | Salt Service Water System Declared Inoperable | On Sunday, August 9, 2015 at 1627 (EDT), with the reactor at 90 percent core thermal power (CTP), the Pilgrim Nuclear Power Station (PNPS) entered a 24-hour shutdown Limiting Condition for Operation Action Statement (LCO-AS) for Salt Service Water (SSW) inlet temperature exceeding the Technical Specification (TS) limit in TS 3.5.B.4. The LCO-AS was subsequently exited at 1653 when the temperature of SSW trended to below the TS limit. Under certain accident conditions, the SSW system is required to provide cooling water to various heat exchangers such as the Reactor Building Closed Cooling Water (RBCCW) and Turbine Building Closed Cooling Water (RBCCW) systems. When the inlet temperature to these supplied loads exceeds the 75 degrees F limit established in the TS, the SSW system is conservatively declared inoperable until the temperature trends below this value. This condition existed for approximately 1/2 hour. When the SSW system was declared operable, the LCO-AS was exited. The SSW temperature is being closely monitored and trended on a continuous basis. This event has no impact on the health and safety of the public. The licensee has notified the NRC Senior Resident Inspector. This notification is being made in accordance with 10 CFR 50.72 (b) (3) (v) (D) due to an event or condition that could have prevented fulfillment of a safety function. The licensee will be notifying the Commonwealth of Massachusetts Emergency Management Agency. The licensee returned the unit to 100 percent power at approximately 2000 EDT. | |
| ENS 51279 | 31 July 2015 14:42:00 | 10 CFR 26.719, FFD Reporting requirements | Fitness for Duty Report Involving a Supervisor | A supervisory employee failed a pre-access Fitness-for-Duty (FFD) test required for reinstatement of site access. The employee did not have unescorted access to the site at the time of the test. The employee has been assigned a mandated EAP referral, and his site access has been revoked pending review by the medical review officer. The NRC Resident Inspector has been informed. Reportable per 10 CFR 26.719 and Entergy Procedure EN-NS-102, Fitness for Duty Program. | |
| ENS 51267 | 27 July 2015 16:29:00 | 10 CFR 26.719, FFD Reporting requirements | Fitness for Duty Report Involving a Licensed Employee | A licensed employee violated the site Fitness-for-Duty (FFD) policy. The employee's plant access has been denied. The NRC Resident Inspector has been informed. | |
| ENS 51087 | 22 May 2015 14:02:00 | 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation | Manual Reactor Scram Due to Loss of Condenser Vacuum | On Friday, May 22, 2015 at 1002 EDT, with the Reactor Mode Select Switch in the Start-Up position and the reactor at approximately 3 percent core thermal power, while returning to power from Refueling Outage Number 20, a manual reactor scram was inserted due to degrading main condenser vacuum. The cause of the degraded vacuum is currently under investigation. Following the reactor scram, all rods were verified to be fully inserted and no Emergency Operating Procedure entry conditions existed. All plant systems responded as designed. Currently reactor pressure is being maintained at 400 psig with the Mechanical Hydraulic Control System (turbine by-pass valves). Reactor water level is being maintained in normal bands with the Condensate and Feedwater System. Off-site power is being supplied to the station by the Startup Transformer (normal power supply for shutdown operations). This event had no impact on the health and/or safety of the public. The NRC Resident Inspector is on-site and has been notified. The licensee has notified the Massachusetts Emergency Management Agency. The licensee will be issuing a press release.
The following was provided by the licensee as clarifying information to the first paragraph of the original event notification: As a conservative measure, the operating crew had previously started reducing power from 20 percent core thermal power when it was first noticed that main condenser vacuum was degrading. This was well before any low condenser vacuum alarms were received. During the shutdown, after already securing the main turbine, the operating crew established benchmark values for degrading condenser vacuum for a normal plant shutdown and for a manual reactor scram should vacuum continue to decline to preclude an automatic scram. The licensee notified the NRC Resident Inspector. Notified R1DO (Dwyer). | |
| ENS 51174 | 13 May 2015 04:00:00 | Information Only | Voluntary Report - Information Only | On May 13, 2015, with the unit shut down and the mode switch in Refuel, during the performance of plant procedure 3.M.2-12.4, 'Backfilling Reference Lines for Racks C2205, C2275, and C2251' a full reactor scram occurred. The scram occurred at Step (26)(b) of Attachment #1 of the procedure. The plant had been shut down for refueling for a couple of weeks or more and was in 'cold' condition. This event was evaluated for potential reportability under both 10 CFR 50.72 and 50.73 and found to be not reportable as either a prompt report or LER. The following 'System Actuation' sections were most applicable. 10CFR50.72(b)(2)(iv)(B) Any event or condition that results in actuation of the reactor protection system (RPS) when the reactor is critical - Plant Response: Pilgrim was not critical at the time of the event. 10CFR50.72(b)(3(iv)(A) Any event or condition that results in valid actuation of any of the systems listed in paragraph (b)(3)(iv)(B) - Plant Response: Pilgrim was in the process of refilling reference legs as part of restoration from the refueling outage. This was not a valid RPS signal. 10CFR50.73(a)(2)(iv)(A) Any event or condition that resulted in manual or automatic actuation of any of the systems listed in paragraph (a)(2)(iv)(B) of this section, except when: (2) The actuation was invalid and; (i) Occurred while the system was properly removed from service - Plant Response: This was an invalid actuation that occurred when the system was already properly removed from service. All requirements of plant procedures for removing equipment from service had been met. That included required clearance documentation, equipment and control board tagging and properly positioned valves and power supply breakers. Although this event is not reportable, we are making a courtesy notification to the NRC Operations Center. | |
| ENS 50790 | 5 February 2015 18:00:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Loss of Sea Water Intake Bay Level Instrumentation Due to Loss of Instrument Air | On January 27, 2015, during winter storm JUNO, there was a loss of instrument air at the Pilgrim Nuclear Power Station (PNPS). Follow-up evaluations of the plant events that occurred on that day revealed that the loss of instrument air resulted in a loss of water level indicators in the seawater intake bays. The affected instruments, LI-3831 A/B, are utilized in assessing conditions for entry into the Emergency Action Levels. PNPS Emergency Plan Implementing Procedure (EPIP) EP-IP-100.1 specified a compensatory action of 'visual inspection required' should these instruments be unavailable. However, there was not a clear linkage between the EPIP compensatory actions and the operations procedure for loss of instrument air. Neither the EPIP nor operations procedure identified the specific actions necessary to perform the local monitoring action. Based on the above, we have concluded that this event was reportable pursuant to 10CFR50.72(b)(3)(xiii), Any event that results in a major loss of emergency assessment capability. The review of the event revealed actual sea water levels in the intake bay did not meet plant specified EAL entry conditions at any time during the winter storm and therefore no plant equipment was impacted. The capability to assess intake bay water level locally in the intake bay was available. Subsequent to the winter storm event, the instrument air system and sea water bay level instrumentation were restored to service. Public health and safety were not adversely affected. The licensee has notified the NRC Senior Resident Inspector. The licensee will notify the Commonwealth of Massachusetts. | |
| ENS 50771 | 27 January 2015 14:48:00 | 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | Loss of High Pressure Coolant Injection | On Tuesday, January 27, 2015, at 0948 EST, with the Reactor Mode Select Switch (RMSS) in the Shutdown position and Pilgrim Nuclear Power Station (PNPS) at 0% core thermal power, the High Pressure Coolant Injection (HPCI) system was isolated by the main control room operating crew and declared INOPERABLE. HPCI had been in service for reactor pressure control following the automatic reactor scram experienced during winter storm 'Juno' reported in EN# 50769. It appears there was a malfunction of the HPCI turbine gland seal condenser blower or associated condensate pump. Reactor pressure control was transitioned to the safety relief valves and the reactor cooldown was continued. The plant is stable. The Emergency Diesel Generators are powering the safety related 4KV buses and reactor water level is being maintained by the Reactor Core Isolation Cooling (RCIC) system. HPCI is required to be OPERABLE in accordance with Technical Specification 3.5.C.1. Since HPCI is a single train system, the INOPERABILITY is reportable in accordance with 10CFR50.72(b)(3)(v)(D). The cause of the HPCI malfunction is not known at this time and troubleshooting continues. This event had no impact on the health and/or safety of the public. The USNRC Senior Resident Inspector has been notified. Shutdown cooling is in service. | 05000293/LER-2015-001 |
| ENS 50769 | 27 January 2015 09:02:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation 10 CFR 50.72(b)(3)(iv)(A), System Actuation | Automatic Reactor Scram on Turbine Trip Due to Loss of Offsite Power | On Tuesday January 27, 2015 at 0402 hours, with the Pilgrim Nuclear Power Station (PNPS) Reactor Mode Select Switch (RMSS) in Run and reactor power approximately 52% an automatic reactor scram signal was received due to the automatic trip of the main turbine that was initiated by the opening of the main generator breaker, ACB-104. The event occurred during winter storm 'Juno.' Prior to the event off-site transmission Line 355 was de-energized due (to) weather conditions and its associated PNPS switchyard breakers (ACB-105, a main generator breaker and ACB-102), were open. Per station procedures, reactor power was being lowered, a reactor protection system bus had been placed onto a back-up power supply, the Emergency Diesel Generators had been started and were powering the associated safety related 4 KV buses. The second off-site transmission Line 342 de-energized and the associated PNPS switchyard breakers (ACB-104 main generator breaker and ACB-103) opened. The Shutdown Transformer off-site power supply has remained available throughout this event. All control rods were verified to be fully inserted. Per plant design, Primary Containment Isolation System (PCIS) Group lI sampling systems, Group VI Reactor Water Clean-up (RWCU) system and Reactor Building Isolation System (RBIS) isolations occurred. Currently, the EDG's are powering the safety related 4KV buses, reactor water level is being maintained by the Reactor Core Isolation Cooling (RCIC) system and reactor pressure is being maintained by High Pressure Coolant Injection (HPCI) system. The station is conducting a plant cool down at this time. All systems responded as designed with the exception of a non-safety-related diesel air compressor, K-117 that failed to start. The licensee will notify the State and local governments and plans on issuing a press release. The NRC Resident Inspector has been informed. | 05000293/LER-2015-001 |
| ENS 50356 | 12 August 2014 06:38:00 | 10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | Hpci Potential Inoperability Discovered During Post Maintenance Testing | At 0238 hours (EDT) on Tuesday, August 12, 2014, with Pilgrim Station at 100 percent power in the Run Mode with reactor coolant pressure at approximately 1025 psig and the High Pressure Coolant Injection (HPCI) System previously removed from service for maintenance, a condition with the potential to impact the operability of the HPCI System was discovered. The HPCI System was being operated in accordance with plant procedures to complete post maintenance test requirements. Upon HPCI initiation, the indicated flow on HPCI Flow Indicator FI-2340-1-1 was 0 Gallons Per Minute (GPM) with the flow controller in the manual mode. The indicated flow on HPCI Flow Indicator Fl-2340-1-1 remained at 0 GPM throughout the duration of the surveillance. Alternate flow indication indicated the expected HPCI flow rate. The flow controller in manual was capable of controlling at the demanded HPCI turbine speed. The HPCI turbine speed was manually varied with a corresponding change in the HPCI flow computer point reading. Activities to restore the flow indicator capability are in progress. The plant is in a safe condition and plant personnel are investigating the cause of the flow indicator issue. The NRC Resident Inspector has been informed of this notification. This notification is being made in accordance with 10 CFR 50.72(b)(3)(v)(B) and 10 CFR 50.72(b)(3)(v)(D). The licensee will be notifying the state.
Subsequent investigation determined that HPCI Flow Instrument SQRT-2340-10 output signal was 0 mA and did not change in response to the actual HPCI flow rate. With the SQRT-2340-10 output signal at 0 mA, the HPCI Flow controller would demand maximum HPCI injection flow in the AUTOMATIC control mode. Circuitry within the control system limits the maximum HPCI flow to 5250 GPM at a turbine speed of 4165 RPM. Engineering analysis has concluded that the HPCI pump operating limits (net positive suction head and low pressure suction trip) would not be exceeded in a maximum HPCI flow state. Therefore, the HPCI System was operable and capable of performing its residual heat removal and accident mitigation functions. Therefore, the initial 50.72(b)(3)(v)(B) and 10CFR50.72(b)(3)(v)(D) report is being retracted. The (NRC) Resident Inspector has been informed of this notification retraction. Notified the R1DO (Krohn). | |
| ENS 50273 | 11 July 2014 12:23:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Loss of Assessment Capability - Loss of Power to the Plant Process Computer | At 0823 EDT on Friday, July 11, 2014, the Pilgrim Nuclear Power Station (PNPS) determined that the plant process computer and, therefore, the in-plant Safety Parameter Display System (SPDS) was not functioning as designed due to a loss of power. The SPDS provides numerous plant parameters, some of which are credited for emergency assessment capability. The site has determined that this constitutes a major loss of assessment capability. Immediate actions were taken to restore the system to functional status and applicable plant procedures were entered to determine temporary mitigating actions. Power was subsequently restored at approximately 1030 EDT via an alternate supply, and SPDS has been restored to normal operation. This event had no impact on the health and/or safety of the public. This notification is conservatively being made in accordance with 10 CFR 50.72 (b)(3)(xiii). There is no impact to plant operations. The licensee notified the NRC Resident Inspector and will notify the State. | |
| ENS 50134 | 23 May 2014 16:10:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification - Release of Hydrogen Gas in Excess of Reportable Quantity | At 1210 EDT on Friday, May 23, 2014, the Massachusetts Department of Environmental Protection and the Plymouth Massachusetts Fire Department were notified of a hydrogen release in accordance with plant procedures and 310CMR40.300, Massachusetts Contingency Plan Notification for Oil and Hazardous Material; Identification and Listing of Oil and Hazardous Material. This was due to a release of hydrogen gas to the environment exceeding the reportable quantity of ten pounds. The release was from the generator hydrogen cooling system. There was no plant damage. Hydrogen system pressure has been restored to the normal operating band and is stable. The cause of the event is under investigation. This event posed no danger to the health and safety of plant personnel or members of the general public. The NRC Resident Inspector has been notified. | |
| ENS 49905 | 12 March 2014 17:15:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Loss of Communication - Federal Telephone System (Fts) | At 1315 (EDT) on Wednesday March 12, 2014, while performing monthly communications testing, Pilgrim Nuclear Power Station (PNPS) discovered that portions of the Federal Telephone System (FTS) were not functioning as designed. Specifically, the Emergency Notification System (ENS), is not available from the Control Room or Technical Support Center/ Operations Support Center (TSC/OSC) while the Health Physics Network (HPN), the Reactor Safety Counterpart Link (RSCL), and the Protective Measures Counterpart Link (PMCL) are not currently available from the Technical Support Center/ Operations Support Center (TSC/OSC). All four of these systems were confirmed to be available from the Emergency Operations Facility (EOF). The initial investigation has determined that the failure has not impacted the entire FTS, but may have the potential to impair the licensee's ability to communicate in the event of an emergency. Immediate actions are being taken to restore the system to functional status and applicable plant procedures have been entered to determine any further mitigating actions. Members of the Emergency Response Organization have been notified of the failures and the need to utilize commercial phone lines as a compensatory action. The NRC Operations Center has been contacted and informed of these communication system failures. It cannot be determined at the time of this notification as to when the system will be restored to full functional status. This event had no impact on the health and/or safety of the public. The licensee has notified the NRC Senior Resident Inspector. This notification is conservatively being made in accordance with 10 CFR 50.72 (b)(3)(xiii) due to the loss of certain emergency response communication capabilities as provided by the FTS. The NRC Resident Inspector has been notified. The licensee will notify the state.
Federal Telephone System (FTS) communications testing was completed at 1130 EDT on March 14, 2014. The FTS System has been restored to full functional status. The Emergency Response Organization (ERO) has been informed. The licensee has notified the NRC Senior Resident Inspector and the Commonwealth of Massachusetts. Notified R1DO (Ferdas). | |
| ENS 49605 | 3 December 2013 18:30:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Loss of Emergency Communications Capability- Ep Conferencing Lines Unavailable | At approximately 1330 (EST) on Tuesday, December 03, 2013, while performing a table top drill, Pilgrim Nuclear Power Station (PNPS) discovered that EP (Emergency Preparedness) bridge conferencing lines were unavailable. The conference lines affected included the mitigation line, plant data phone, radiation data phone, emergency conferencing line, and the back up conference bridge line. Reviews to determine the cause of the event and efforts to restore the system are ongoing. The licensee has determined the Emergency Plan to be functional based on other communication methods that are available between onsite and offsite facilities. These include direct telephone lines, portable handheld radios, satellite phones and cell phones. Immediate actions to establish compensatory conferencing lines have been completed. On-going actions are in-progress to ensure procedure instruction is provided at each facility to enable use of the compensatory conference lines. At the time of this report, the plant is currently operating at 82% power due to a planned power maneuver unrelated to the reported communication event. The licensee has notified the NRC Senior Resident Inspector (and will notify the Commonwealth of Massachusetts). This notification is being made in accordance with 10 CFR 50.72(b)(3)(xiii) due to the loss of emergency response communication capability.
The primary communications method has been restored. The backup communications method should be restored tomorrow. The licensee will notify the NRC Resident Inspector. Notified the R1DO (Cook). | |
| ENS 49454 | 19 October 2013 07:31:00 | 10 CFR 50.72(b)(3)(iv)(A), System Actuation | Group 1 Isolation Due to High Reactor Water Level | On Saturday, October 19, 2013 at 0331 hours, with the reactor critical at approximately 1% core thermal power and the mode switch in start-up, a high reactor water level condition resulted in a main turbine trip and a valid Group 1 isolation signal. As a result, the Main Steam Isolation Valves (MSIVs) closed. The plant was in start-up from a forced outage. The initial plant conditions were reactor pressure at approximately 280 psig with a corresponding reactor coolant temperature for that pressure. Currently reactor pressure and water level are being maintained with the MSIVs closed in normal bands. The reactor is being cooled down in preparation for operation in shutdown cooling. Off-site power is supplying station power from the Start-up Transformer (normal power supply for shutdown operations). All plant systems responded as designed. The cause of the increase in reactor water level is currently under investigation. This event had no impact on the health and/or safety of the public. The USNRC Senior Resident Inspector has been notified. | 05000293/LER-2013-010 |
| ENS 49296 | 22 August 2013 11:55:00 | 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation 10 CFR 50.72(b)(3)(iv)(A), System Actuation 10 CFR 50.72(b)(2)(iv)(A), System Actuation - ECCS Discharge | Reactor Protection Actuation (Scram) | On Thursday, August 22, 2013 at 0755 hours (EDT), with the reactor critical at approximately 98% core thermal power, and the mode switch in RUN, a manual reactor scram was inserted due to lowering reactor water level. The cause of the lowering reactor water level was due to the trip of all three Feedwater Pumps. The cause of the Feedwater Pump trip event is currently under investigation. Following the reactor scram, all control rods were verified to be fully inserted. All 4kV busses transferred to the Startup Transformer as designed. Following the scram the reactor water level lowered to +12 inches initiating the Primary Containment Isolation System (Group II, Reactor Building Isolation System (RBIS); and Group VI - Reactor Water Cleanup System) automatically as per design. Reactor water level lowered to -46 inches initiating Primary Containment Isolation System Group I - Main Steam Isolation Valves (MSIVs); Emergency Core Cooling Systems (ECCS) actuated which included automatic start and injection of the High Pressure Coolant Injection (HPCI) System and the Reactor Core Isolation Cooling (RCIC) System and an automatic start of the Emergency Diesel Generators as designed. Reactor water level was promptly restored to normal level. Currently a cooldown is in progress with reactor pressure is being maintained by the HPCI System operating in the pressure control mode and reactor water level is being maintained by the RCIC System. Reactor Water Clean-up System and normal reactor building ventilation have been restored. Off-site power is being supplied to the station by the Start-up Transformer (normal power supply for shutdown operations). This event had no impact on the health and/or safety of the public. The USNRC Senior Resident Inspector has been notified. This 4-hour notification is being made in accordance with 10 CFR 50.72 (b)(2)(iv)(A) and (B). The plant is transferring from decay heat removal to the torus to decay heat removal to the main condenser. Reactor pressure is 371 psig. Initial indications are that a main feedwater power supply breaker tripped. | 05000293/LER-2013-008 |
| ENS 49201 | 17 July 2013 14:54:00 | 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | Salt Service Water System Declared Inoperable | On Wednesday, July 17, 2013 at 1054 hours EDT, with the reactor at 100% core thermal power (CTP) the Pilgrim Nuclear Power Station (PNPS) entered a 24-hour shutdown Limiting Condition for Operation (LCO) for Salt Service Water (SSW) inlet temperature exceeding the Technical Specification (TS) limit in TS 3.5.B.4. The LCO was subsequently exited at 1625 hours when the temperature of SSW trended to below the TS limit. Under certain accident conditions the SSW system is required to provide cooling water to the Reactor Building Closed Cooling Water (RBCCW) system heat exchanger. When the inlet temperature to this supplied load exceeds the 75 (degrees) F limit established in the TS, the SSW system is declared inoperable until the temperature trends below this value. This condition existed for approximately 5-1/2 hours and the SSW system was declared operable and the LCO exited. A maximum temperature of 75.5 (degrees) F was recorded during this period. At 1230 hours a power reduction was conducted to improve secondary plant parameters and Rx power is currently 85%. The SSW temperature is being closely monitored and trended on a continuous basis. This event has no impact on the health and safety of the public. The licensee has notified the NRC Senior Resident Inspector." The licensee will notify the Commonwealth of Massachusetts. | |
| ENS 49196 | 15 July 2013 20:52:00 | 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | Salt Service Water System Declared Inoperable | On Tuesday, July 16, 2013 at 1652 (EDT), with the reactor at 100% core thermal power (CTP) the Pilgrim Nuclear Power Station (PNPS) entered a 24-hour shutdown Limiting Condition for Operation (LCO) for Salt Service Water (SSW) inlet temperature exceeding the Technical Specification (TS) limit in TS 3.5.B.4. The LCO was subsequently exited at 1830 hours when the temperature of SSW trended to below the TS limit. Under certain accident conditions the SSW system is required to provide cooling water to the Reactor Building Closed Cooling Water (RBCCW) system heat exchanger. When the inlet temperature to this supplied load exceeds the 75 (degrees) F limit established in the TS, the SSW system is declared inoperable until the temperature trends below this value. This condition existed for approximately 1-1/2 hours and the SSW system was declared operable and the LCO exited. A maximum temperature of 75.3 (degrees) F was recorded during this period. The SSW temperature is being closely monitored and trended on a continuous basis. This event has no impact on the health and safety of the public. The licensee has notified the NRC Senior Resident Inspector. SSW temperature varies with tidal movement. | 05000293/LER-2013-007 |
| ENS 49189 | 15 July 2013 04:29:00 | 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Unusual Event Declared Due to Loss of Control Room Annunciators | The licensee declared a Notice of Unusual Event resulting from a loss of control room annunciators for greater than 15 minutes. The EAL Condition is SU 4.1. Compensatory measures have been established per Abnormal Operating Procedures. The plant continues to operate at 100 percent power. The licensee has called for support staff to troubleshoot the issue. No other major components are out of service. The licensee has notified the NRC Resident Inspector. Notified DHS SWO, FEMA, DHS NICC and the Nuclear SSA via email. * * * UPDATE FROM KEVIN O'ROURKE TO PETE SNYDER AT 0205 EDT ON 7/15/13 * * * Annunciator indication has returned for some time and appears to be working. Engineering and electrical instrumentation and control staff are onsite to troubleshoot but have not established any cause. The licensee remains in the Unusual Event until additional confidence can be established in annunciator indication. Notified R1DO (Cook).
The NOUE declared on July 15, 2013 at 0029 EDT hours due to loss of main control room annunciation was terminated on July 16, 2013 at 2310 EDT hours when the annunciation system was declared functional. Plant personnel and vendors have completed diagnostic checks and testing, system voltages are normal, and the annunciator system is working normally. The licensee has notified the NRC Resident Inspector. Notified R1DO (Gray), NRR EO (Hiland), IRD MOC (Grant), DHS SWO, FEMA, DHS NICC and the Nuclear SSA via email. | |
| ENS 49187 | 11 July 2013 14:30:00 | 10 CFR 26.719, FFD Reporting requirements | Fitness-For-Duty Report Involving a Non-Licensed Supervisor | A non-licensed employee supervisor had a confirmed positive for a banned substance during a random fitness-for-duty test. The employee's access to the plant has been terminated pending an ongoing investigation. The licensee informed the NRC Resident Inspector. |