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The query [[Category:ENS Notification]] [[Site::Pilgrim]] [[Scram::+]] was answered by the SMWSQLStore3 in 0.3479 seconds.


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 Entered dateSiteRegionScramReactor typeEvent description
ENS 5407118 May 2019 02:09:00PilgrimNRC Region 1Manual Scram

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 536485 October 2018 15:39:00PilgrimNRC Region 1Automatic ScramOn 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 531474 January 2018 17:57:00PilgrimNRC Region 1Manual ScramGE-3On 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 522236 September 2016 11:24:00PilgrimNRC Region 1Manual ScramGE-3On 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 5133822 August 2015 20:14:00PilgrimNRC Region 1Automatic ScramGE-3

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 5108722 May 2015 13:36:00PilgrimNRC Region 1Manual ScramGE-3

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.

  • * * UPDATE FROM EVERETT PERKINS TO DONALD NORWOOD AT 1110 EDT ON 5/24/2015 * * *

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 5077127 January 2015 16:56:00PilgrimNRC Region 1Automatic ScramGE-3On 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.
ENS 5076927 January 2015 06:41:00PilgrimNRC Region 1Automatic ScramGE-3On 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.
ENS 4929622 August 2013 11:39:00PilgrimNRC Region 1Manual ScramGE-3On 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.
ENS 4892315 April 2013 02:01:00PilgrimNRC Region 1Manual ScramGE-3On Sunday, April 14, 2013 at 2217 hours, with the Pilgrim Nuclear Power Station (PNPS) Reactor Mode Select Switch (RMSS) in Start-up, the turbine generator previously removed from service, and the reactor sub-critical on Intermediate Range Monitors Range 2 and lowering, a manual reactor scram was inserted due to reactor pressure lowering beyond established control bands. At the time of the manual reactor scram PNPS was conducting a planned reactor shutdown to commence refueling outage (RFO) -19. All control rods fully inserted and Primary Containment Isolation System Group II (Reactor Building) and Group VI (Reactor Water Cleanup System) actuations occurred as designed due to the expected reactor water level shrink associated with the scram signal. All plant systems responded as designed. Off-site power was unaffected and was supplied by the start-up transformer (normal power supply for refuel and reactor shutdown operations). The Main Steam Isolation Valves (MSIV) were manually closed to terminate the reactor pressure reduction and the High Pressure Coolant Injection (HPCI) system was manually started in the reactor pressure control mode. The Reactor Protection System (RPS) was reset as were the reactor building and reactor water clean-up system isolation signals. Currently, the plant cooldown is continuing with the HPCI system in pressure control and reactor water level being maintained within normal bands with the condensate and feedwater system. The cause of the lowering reactor pressure has not been determined and remains under review. This event had no impact on the health and/or safety of the public. This 8-hour notification is being made in accordance with 10 CFR 50.72 (b)(3)(iv)(A). The NRC Senior Resident Inspector has been notified. The licensee will also be notifying state authorities.
ENS 487368 February 2013 22:50:00PilgrimNRC Region 1Automatic ScramGE-3

Pilgrim Station scrammed on a loss of offsite power. All systems performed as designed. Groups I, II, VI went to completion. Reactor Core Isolation Cooling (RCIC) is injecting to the vessel controlling level. High Pressure Coolant Injection is in pressure control and slowly cooling down. Offsite power was lost multiple times. The Startup Transformer has been declared inoperable. The Unusual Event was declared under EAL SU 1.1 based on loss of offsite power greater than 15 minutes (at 2200 EST). The licensee originally experienced an automatic reactor scram at 2117 EST due to a load reject with a turbine trip/reactor scram due to loss of power. Offsite power availability has been fluctuating in and out to the site. The licensee states that all systems are functioning as required. All rods fully inserted and the reactor is stable in Mode 3. Both Emergency Diesel Generators are providing power to the safety related buses. The loss of offsite power is believed to be weather related. The licensee has notified the State and local authorities and the NRC Resident Inspector. Notified DHS SWO, FEMA, USDA, HHS, DOE, DHS NICC, EPA, and NuclearSSA via email.

  • * * UPDATE FROM PAUL GALLANT TO VINCE KLCO AT 2/10/13 AT 1108 EST* * *

Pilgrim terminated the Unusual Event and has transitioned to recovery effective at 10:55 AM on 02/10/2013. Offsite power has been restored to safety-related and non-safety-related electrical buses through the station Startup Transformer via a single 345 KV line. The other two offsite power sources remain out of service. The emergency diesel generators have been secured and are in standby. Residual heat removal is in shutdown cooling mode maintaining the reactor in cold shutdown. Fuel Pool Cooling is in service with fuel pool coolant temperatures trending down. The licensee notified State, local authorities and the NRC Resident Inspector. Notified R1 RA (Dean), R1DO (Powell), NRR DIR(Leeds) NRR EO (Evans) and NSIR IRD (Marshall). Notified DHS SWO, FEMA, USDA, HHS, DOE, DHS NICC, EPA, and NuclearSSA via email.

ENS 4866410 January 2013 19:05:00PilgrimNRC Region 1Manual ScramGE-3On Thursday, January 10, 2013 at 1534 hour (EST), with the reactor at 100% core thermal power, both recirculation pumps spuriously tripped and a manual reactor scram was inserted as required by station procedures. The cause of the recirculation pump trip is under investigation. Following the reactor scram, all rods were verified to be fully inserted and the Primary Containment Isolation System Group II (Reactor Building) and Group VI (Reactor Water Cleanup System) actuations occurred as designed due to the expected reactor water level shrink associated with the scram signal. All other plant systems responded as designed. Currently reactor pressure is being maintained between 900 and 1050 psig with the Mechanical Hydraulic Control System (turbine by-pass valves). The Reactor Protection System has been reset; Reactor Water Cleanup System and normal reactor building ventilation have been restored. 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 Start-up Transformer (normal power supply for shutdown operations) and the switchyard ring bus has been restored. This event had no impact on the health and/or safety of the public. The USNRC Senior Resident Inspector is on-site and has been notified. This 4-hour notification is being made in accordance with 10 CFR 50.72 (b)(2)(iv)(B). The scram was uncomplicated and decay heat is being released to the main condenser via the turbine by-pass valves.
ENS 4794522 May 2012 16:33:00PilgrimNRC Region 1Manual ScramGE-3On Tuesday, May 22, 2012 at 1311 hours (EDT), with the reactor at approximately 35% core thermal power, during a planned power reduction to support thermal backwash of the main condenser, 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 the Primary Containment Isolation System Group II (Reactor Building) and Group VI (Reactor Water Cleanup System) actuations occurred as designed due to the expected reactor water level shrink associated with the scram signal. Standby Gas Treatment System Train 'B,' which is designed to shutdown 65 seconds after the Group II signal is received if the Standby Gas Treatment Train 'A' is in service, continued to operate until manually secured. With this exception, all other plant systems responded as designed. Currently reactor pressure is being maintained at 920 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 Start-up Transformer (normal power supply for shutdown operations). This event had no impact on the health and/or safety of the public. The NRC Senior Resident Inspector has been notified." The licensee has notified the Massachusetts Emergency Management Agency.
ENS 4473519 December 2008 21:52:00PilgrimNRC Region 1Automatic ScramGE-3On December 19, 2008, at 1831 hours with the reactor at 100% core thermal power (CTP) an automatic reactor scram occurred. It appears the scram occurred as a result of a load reject experienced during a severe winter storm. Three of the four safety relief valves opened in response to the event. Primary Containment Isolation System (PCIS) Group 2 (sample valves) and Group 6 (reactor water cleanup system) and the reactor building isolation system (RBIS-secondary containment) isolated as designed (all have since been restored) on the reactor water level +12 inches setpoint due to normal vessel shrink. Initial review indicates all safety-related systems responded as designed. Off-site power has been maintained; however the two 4kv safety related buses (A5&A6) were conservatively placed on the station emergency diesel generators due to potential grid stability concern. Currently, the reactor mode select switch (RMSS) is in the Shutdown position; the reactor scram has been reset; the reactor is being maintained at approximately 940 psig, with pressure being maintained by the main turbine by-pass valves; and reactor water level is being maintained at normal levels of 29 inches with the main condensate and feedwater system. Station maintenance personnel are assessing the status of the station switchyard. Once this activity is complete the duration of the forced outage and recovery plans will be determined. All control rods fully inserted on the scram. The licensee has notified the NRC Resident Inspector.
ENS 4347910 July 2007 22:55:00PilgrimNRC Region 1Automatic ScramGE-3During a planned power reduction to support thermal backwash of the main condenser, an automatic reactor scram resulted from a main turbine trip. The cause for the turbine trip is currently under investigation. Following the reactor scram, the expected reactor level shrink resulted in valid group 2, Reactor Building Ventilation, and group 6, Reactor Water Cleanup System isolations. All safety systems and equipment functioned as designed. A schedule for plant restart has not yet been determined. All control rods fully inserted and no safety relief valves lifted from the scram. Minimum level after the scram was -10 inches. Decay heat is being removed using the main turbine bypass valves to the main condenser and maintaining level using normal reactor feed water. The plant is using the normal shut down electrical lineup and slowly cooling down (currently at 820 psi). The licensee notified the NRC Resident Inspector.
ENS 4324517 March 2007 21:11:00PilgrimNRC Region 1Manual ScramGE-3On March 17 2007, at approximately 1658 EDT, Group 2 (Reactor Building Ventilation Isolation) and Group 6 (RWCU Isolation) automatic containment isolation signals were received due to low reactor water level following the insertion of a manual scram signal. The manual scram signal was inserted following the reaching of internal administrative limits on changes in unidentified drywell leakage. The receipt of these isolation signals is not unusual following the insertion of a scram signal. The reactor was manually shutdown due to reaching internal administrative limits on changes in unidentified drywell leakage. Prior to the manual shutdown, the leakage had not reached the applicable Technical Specification limits. Drywell leakage as of 1800 EDT was 1.3 GPM identified and 2.59 GPM unidentified with the unit in Hot Shutdown Mode. All safety systems responded as expected. The plant is in a stable condition. Investigation is continuing. The licensee notified the NRC Resident Inspector.
ENS 4241413 March 2006 21:21:00PilgrimNRC Region 1Manual ScramGE-3During a power ascension, the non-safety Augmented Offgas System experienced a failure which caused a Recombiner high temperature condition. To protect components of the non-safety Augmented Offgas System, station procedures require a manual scram of the reactor when this condition occurs. Station procedures were followed and the reactor was manually scrammed at 18:08. All rods fully inserted and all safety systems performed per design. Primary containment isolation systems responded properly resulting in an automatic isolation of Primary Containment Isolation System Groups 2 and 6 valves and a Reactor Building Isolation due to the transient low reactor water level condition caused by the scram. The plant is in a stable condition. Investigation is continuing. No safety valves lifted on the scram, decay heat is being removed with the bypass valve, normal feed and condensate are maintaining reactor water level, and the electrical grid is stable on the startup transformer. The licensee notified the NRC Resident Inspector.