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Start date | Reporting criterion | Title | Event description | System | LER | |
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ENS 40049 | 6 August 2003 20:30:00 | 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | Unanalyzed Condition | On 8/06/2003 at 1630 hours, the Beaver Valley Power Station (BVPS) Unit 2 control room was notified by Engineering that the manual operator actions specified in Unit 2 post-fire procedures are not adequate for defeating a potential fire-induced spurious operation of the Power Operated Relief Valves (PORVs). The procedure step de-energizes the PORVs by opening breakers at the d-c distribution panel. This action alone would not be sufficient to prevent a cable-to-cable hot short from re-energizing the circuit since the de-energized circuit is routed in cable trays with other energized circuits in the affected fire areas. Preliminary reviews have identified the following potentially affected fire areas: CB-1 Control Building Instrumentation and Relay Area CB-2 Control Building Cable Spreading Room CB-3 Control Building Main Control Room CB-6 Control Building West Communication Room CT-1 Cable Tunnel CV-1 Cable Vault and Rod Control Area SB-1 Emergency Switchgear Room (Orange) RC-1 Reactor Containment An hourly roving fire watch patrol has been established for the affected fire areas as compensatory measures, with the exception of the Main Control Room and the Reactor Containment area, until the condition is fully evaluated and resolved. The Main Control Room is continuously manned and does not require an hourly fire watch patrol. The Reactor Containment area is not accessible during normal power operations and, as such, compensatory measures for this area will include a once-per-shift verification of remote instrumentation by operations personnel to confirm that there are no abnormal conditions or indications for this area. This condition was discovered during the review of manual operator actions for fire-induced spurious operations to confirm the safe shutdown circuit analysis is consistent with the manual actions identified in the procedures. This condition is being reported pursuant to 10 CFR 50.72(b)(3)(ii) as an unanalyzed condition that significantly degraded plant safety since the failure to assure the PORVs remain in the closed position could result in the failure to meet the fire protection safe shutdown criteria. BVPS Unit 2 was licensed to the NUREG 0800 Standard Review Plan 9.5.1 "Fire Protection Program", and License Condition 2.F requires compliance to the provisions of the approved fire protection program as described in the Final Safety Analysis Report. UFSAR Section 9.5A.1.2.1.6 states that the safe shutdown capability should not be adversely affected by a fire in any plant area which results in spurious actuation of the redundant valves in any one high-low pressure interface line. Even though there is a very low likelihood of multiple shorts causing a spurious PORV actuation in an ungrounded DC circuit, the existing actions to prevent re-energizing the circuit and causing a spurious actuation of the PORVs is not consistent with the NRC guidance for high-low pressure interface valves. The NRC resident inspector has been notified.
On 8/07/03 at 1515, the following additional areas were identified as being potentially affected by this condition: CV-2 Cable vault and Rod Control Area (East) CV-3 Cable vault and Rod Control Area (Elev 755'6") SB-2 Emergency Switchgear Room (Purple) SB-3 Service Bldg. Cable Tray Area ASP Alternative Shutdown Panel Room Interim compensatory measures in the form of hourly roving watch patrols have been expanded to include the above noted areas until the condition is fully evaluated and resolved. The NRC Resident Inspector has been notified. Notified the Region 1 Duty Officer (C. Anderson)
The licensee is retracting this report based on the following: Beaver Valley Power Station (BVPS) Unit No. 2 retracts the notification made on 08/06/2003 at 19:12 hrs regarding the event reported under 10 CFR 50.72(b)(3)(ii)(B) (ENS #40049). The previous notification identified a potential unanalyzed condition that significantly degraded plant safety since the failure to assure the PORVs remain in the closed position could result in the failure to meet the Fire Protection Program safe shutdown criteria. The postulated event for spurious PORV opening due to an external cable-to-cable hot short from a fire was subsequently analyzed. It was determined that since the reactor core does not experience an unrecoverable plant condition and the radiological conditions remained bounded by analyzed DBAs, the plant's safe shutdown capability for a fire event is maintained. Although the now-credible spurious opening of a PORV is a deviation from the current Fire Protection Program criteria, the results of the spurious PORV opening does not adversely impact the plant's safe shutdown capability and hence is not a significant degradation of plant safety. Therefore this condition is not reportable pursuant to either 10 CFR 50.72(b)(3)(ii)(B) nor 50.73(a)(2)(ii)(B) as an unanalyzed condition that significantly degraded plant safety. Compensatory measures in the form of shiftly fire watch patrols for the affected fire areas, with the exception of the Main Control Room and Reactor Containment area (as described in prior notifications), will remain in place until the Fire Protection Program non-conformance issue is dispositioned. The licensee informed the NRC Resident Inspector. Notified R1DO(Gray). | ||
ENS 46208 | 26 August 2010 20:49:00 | 10 CFR 50.72(b)(3)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | Both Trains of High Head Safety Injection Pumps Declared Inoperable | Beaver Valley Power Station Unit No.1, while operating at 100% full power, performed Ultrasonic Testing on the High-Head Emergency Core Cooling System Pump suction headers (6" and 8") following a fill and vent of the 'A' High Head Emergency Core Cooling System Pump. This is required because the fill point for the out of service Emergency Core Cooling System Pump 1CH-P-1A, is it's suction valve from the 8" Charging header, 1CH-19, which was opened. Preliminary indications were such that the 6" suction header was full of water and an air void did exist in the 8" suction header, but the size was indeterminate and had to be calculated by System Engineering. Operations commenced additional monitoring for cavitation of the running charging pump with none identified. Operations then vented the 8" suction header multiple times. At 1649 hours today, the results of the Ultrasonic Test (UT) was provided by System Engineering indicating that an air void existed in the Emergency Core Cooling System Pump 8" Suction header that was in excess of the Acceptance Criteria. At 1649 hours, both trains of High Head Safety Injection pumps were declared Inoperable but remain Available. Technical Specification (TS) 3.5.2 - ECCS operating is not met. Required Action C.1 requires entry of TS LCO 3.0.3 immediately. Per 10CFR50.72(b)(3)(v)(A)&(D) - Event or Condition That Could Have Prevented Fulfillment of a Safety Function, and 10CFR50.72(b)(3)(ii)(B) Unanalyzed Condition, this event is reportable to the NRC within 8 hours. At 1715 additional venting of the 6" Charging Pump suction header revealed no air present. Additional venting of the 8" Charging Pump suction header revealed additional air pockets. The 8" header was then vented multiple times, with a short delay in between each venting, until no air was identified. At 1718, follow up UT on both Charging Pump Suction headers revealed it remained full of water with no voids present. Both trains of High Head Safety Injection are declared OPERABLE restoring compliance to TS LCO 3.0.3 and 3.5.2. Reactor power remained at 100% during these evolutions. The NRC Resident Inspector was informed. | Emergency Core Cooling System | 05000334/LER-2010-001 |
ENS 46421 | 16 November 2010 05:01:00 | 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Control Room Envelope Inoperable Due to Excessive Emergency Core Cooling System Relief Valve Leakage During Eccs Pump Surveillance Testing | Emergency Core Cooling System Control Room Envelope | 05000334/LER-2010-003 | |
ENS 47403 | 2 November 2011 18:30:00 | 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | Unanalyzed Condition Caused by Non-Conforming Fire Barriers | Ongoing field inspections as a result of Industry Operating Experience have identified certain fire barriers that are not in conformance with required tested configurations. Specifically, some of the flexible conduit that penetrates these barriers has a coating that does not exhibit flame retardant characteristics and therefore does not meet the requirements for fire barriers at Beaver Valley Power Station, Unit 1. In the event of a postulated fire, this non-conformance has the potential to affect fire barriers separating the two independent trains required for post fire Safe Shutdown equipment. This issue is being reported per 10CFR 50.72(b)(3)(ii)(B). Compensatory actions have been established in accordance with the approved Fire Protection Program. The NRC Resident Inspector has been notified. | 05000334/LER-2011-001 | |
ENS 50075 | 30 April 2014 15:40:00 | 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | Postulated Hot Short Fire Event Could Adversely Impact Safe Shutdown Equipment | Based on a review of industry operating experience, it was identified that each unit has two un-fused DC control circuits for non safety-related DC motors which are routed from the turbine building through other separate fire areas including the Control Room. The DC breakers used to protect the motor power conductors are insufficient to protect the control conductors for these circuits. It is postulated that a fire induced short in one fire area could adversely impact safe shutdown equipment by overheating the cable and causing a secondary fire in other fire areas where the cable is routed. At Unit 1, cables for the affected circuits are routed in the Turbine Building, Cable Spreading Area and Control Room. At Unit 2, cables for the affected circuits are routed in the Turbine Building, Normal Switchgear, Service Building Cable Tray Area, Cable Vault, Instrument Relay Room, Control Building West Communication Room, Control Building Cable Spreading Area and Control Room. The postulated secondary fires or cable failures are outside the assumptions of each unit's fire protection analysis. A preliminary investigation of the issue indicates that existing fire protection safe shutdown procedures could be used to safely shut down the plant if needed. This condition is reportable as an 8-hour report in accordance with 10 CFR 50.72(b)(3)(ii)(B). Interim compensatory measures will be implemented for affected areas of the plant. The NRC Resident Inspector has been notified. | ||
ENS 52132 | 29 July 2016 01:20:00 | 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | Postulated Fire Event That Could Adversely Impact Safe Shutdown Equipment | A review of the Beaver Valley Unit 2 Fire Protection Safe Shutdown Report (FPSSR) found that a postulated fire had the potential to spuriously open all three individual steam generator atmospheric dump valves in addition to a common residual heat release valve. Previous analysis did not consider all of the valves spuriously opening from a fire. The potential impact of these valves spuriously opening is a cooldown that could adversely affect shutdown margin. Hourly fire tours have been put in place for those fire areas that have the potential to initiate this condition. This condition is reportable as an 8 hour report in accordance with 10 CFR 50.72(b)(3)(ii)(B). The NRC Resident Inspector was notified. This condition is not applicable to Unit 1.
Retraction of EN 52132 'Postulated Fire Event That Could Adversely Impact Safe Shutdown Equipment'. On 07/29/2016, an 8-hour notification (EN 52132) was made describing the discovery of a postulated fire event that could adversely impact safe shutdown equipment, specifically the spurious opening of the three Atmospheric Steam Dump Valves (ASDVs) and the Residual Heat Release (RHR) Valve, simultaneously. This notification was made pursuant to 10 CFR 50.72(b)(3)(ii)(B) as an unanalyzed condition because of the potential effect on shutdown margin. Further engineering evaluation has determined that the required shutdown margin is not challenged by the event, as bounded by previous analysis of a similar scenario as well as validated operator actions. Therefore, this does not result in a reportable condition. The Resident NRC Inspector has been notified. Notified the R1DO (Cook). | Steam Generator | |
ENS 52571 | 23 February 2017 15:40:00 | 10 CFR 50.72(b)(3)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | Potential Tornado Missile Vulnerabilities | In order to address the concerns outlined in RIS (Regulatory Information Summary) 2015-06 'TORNADO MISSILE PROTECTION', an evaluation of tornado missile vulnerabilities and their potential impact on Technical Specification (TS) plant equipment was conducted. This evaluation concluded that the following Structures, Systems, and Components (SSCs) are potentially vulnerable to tornado generated missiles: The BVPS Unit 1 (BV-1) and BVPS Unit 2 (BV-2) Main Steam Safety Valve (MSSVs) discharge flow paths to atmosphere (reference TS 3.7.1) are potentially vulnerable to tornado generated missiles. A tornado could generate missiles capable of striking the exhaust piping of the MSSVs potentially crimping the piping and resulting in reduced flow capacity. In the worst case, all MSSV's could be rendered inoperable. This condition is reportable per 10 CFR 50.72(b)(3)(ii)(B), and 10 CFR 50.72(b)(3)(v)(A). The BV-1 and BV-2 Atmospheric Steam Dumps (ADVs) discharge flow paths to atmosphere (reference TS 3.7.4) are potentially vulnerable to tornado generated missiles. A tornado could generate missiles capable of striking the exhaust piping of the ADVs potentially crimping the piping and resulting in reduced flow capacity. In the worst case, all ADVs could be rendered inoperable. This condition is reportable per 10 CFR 50.72(b)(3)(ii)(B), and 10 CFR 50.72(b)(3)(v)(A). The BV-2 Auxiliary Building tornado missile shield door (A-35-5A), credited for tornado missile protection of the Primary Component Cooling Water (PCCW) system, was found to not be fully closed and latched. A tornado could generate missiles capable of striking the PCCW system with the missile door open rendering both trains of the PCCW system inoperable. This door is now maintained closed and latched except when opened under administrative controls. This condition is reportable per 10 CFR 50.72(b)(3)(ii)(B). The BV-2 Spent Fuel Building tornado missile shield door (F-66-3), credited for tornado missile protection of the irradiated fuel assemblies in the Spent Fuel Pool including the Cask Pit, was found to not be fully closed and latched. This door is now maintained closed and latched except when opened under administrative controls. This condition is reportable per 10 CFR 50.72(b)(3)(ii)(B). The potential tornado missile vulnerabilities for the MSSVs and ADVs (discussed above) are being addressed in accordance with EGM-15-002 Rev 1 and DSS-ISG-2016-01 (NRC enforcement discretion and interim guidance documents). Immediate compensatory measures were taken to reduce the likelihood and mitigate the potential consequences of an onsite tornado generated missiles. The NRC Resident inspector has been notified. | Main Steam Safety Valve | 05000334/LER-2017-002 05000334/LER-2017-001 |
ENS 53419 | 22 May 2018 04:00:00 | 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 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown | En Revision Imported Date 6/22/2018 | EN Revision Text: GAS VOIDS DISCOVERED IN BOTH TRAINS OF LOW HEAD SAFETY INJECTION On 5/22/2018, while operating at approximately 100 percent power, Ultrasonic Testing of the Beaver Valley Power Station (BVPS) Unit 1 Low Head Safety Injection (LHSI) pump suction piping identified gas voids in excess of the acceptable limit for void volume. Both trains of LHSI were declared inoperable. Technical Specification (TS) 3.5.2 for both trains of the LHSI system was entered along with TS 3.0.3 which requires the initiation of a plant shutdown. Time of TS entry was 12:56 (EDT). Plant shutdown was commenced at 15:56 (EDT) in accordance with plant procedures. At 15:59 (EDT) Train 'A' LHSI was restored to operable status, TS 3.0.3 Action was exited and the power reduction was stopped at approximately 99 percent. At 17:43 (EDT) Train 'B' LHSI was restored to operable status, TS 3.5.2 Actions were exited. This is reportable per 10 CFR 50.72(b)(3)(ii) Unanalyzed Condition, 10 CFR 50.72(b)(3)(v) Event or Condition that Could Have Prevented the Fulfillment of a Safety Function and 10 CFR 50. 72(b )(2)(i) TS Required Shutdown. The NRC Resident Inspector has been notified.
Further engineering evaluation has determined that the gas voids that existed at the time of discovery would not have rendered the LHSI (Low Head Safety Injection) system inoperable if it were required to actuate. The engineering evaluation concluded that filling of the containment sump during a Design Basis Accident would result in a void volume reduction such that the void in the LHSI suction piping would not be large enough to significantly impact the operability of the system. Therefore, the system remained operable but degraded. No TSs (Technical Specifications) were required to be entered and no shutdown was required. As such, all three reporting criteria do not apply and are being retracted. The NRC Resident Inspector has been notified. Notified R1DO (Burritt). | ||
ENS 53548 | 12 August 2018 04:00:00 | 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown | En Revision Imported Date 8/17/2018 | EN Revision Text: TECHNICAL SPECIFICATION REQUIRED SHUTDOWN - LOSS OF 480 VOLTAGE EMERGENCY BUS On 8-12-18 at 0158 EDT, Beaver Valley Unit 2 experienced a loss of 480 Volt 2P Emergency Bus. This resulted in a Loss of Safety Function due to the 2-2 Emergency Diesel Generator (EDG) being Inoperable coincident with the Residual Heat Release Valve (2SVS-HCV104). A Technical Specification shutdown is required per LCO 3.0.3. The Licensee also stated they were in an unanalyzed condition due to the EDG and Residual Heat Release Valve being inoperable at the same time. The Licensee is shutting down to Mode 5 (Cold Shutdown). The Licensee is notifying the Resident Inspector. The Licensee will be making a Press Release about the unplanned shutdown.
On 8-12-18 at 0158 (EDT) Beaver Valley Unit 2 experienced a loss of 480 Volt 2P Emergency Bus. Per operational guidance, this was determined to be a Loss of Safety Function due to the Unit 2 Emergency Diesel Generator (EDG) being INOPERABLE coincident with the Residual Heat Release Valve (2SVS-HCV104) 10 CFR 50.72(b)(3)(v)(B) and (D). This was also reported as an Unanalyzed Condition 10 CFR 50.72(b)(3)(ii)(b). No Press Release was performed for this event. The NRC Resident Inspector was notified. At 0410 (EDT) a Technical Specification Shutdown was commenced 10 CFR 50.72(b)(2)(i). At 2011 (EDT) the 480 Volt 2P Emergency Bus was restored and energized. Further evaluation of the event has determined that this event was not an Unanalyzed Condition and did not result in a Loss of Safety Function. The classifications of Unanalyzed Condition and Loss of Safety Function are being retracted. The accuracy of the existing guidance relative to Safety Function has been entered in the Corrective Action Program and interim actions have been taken to provide accurate guidance. Notified R1DO (Young) via email. | Emergency Diesel Generator | |
ENS 54366 | 2 November 2019 19:15:00 | 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | Refueling Water Storage Tank Declared Inoperable Due to Low Level | At 1515 on November 2, 2019, the Refueling Water Storage Tank (RWST) was declared inoperable due to a Low Head Safety Injection relief valve discharging to the Safeguards Sump during routine surveillance testing. The leakage from the Low Head Safety Injection system in conjunction with a postulated Design Basis Accident (DBA) Loss of Coolant Accident (LOCA) with transfer to Safety Injection Recirculation may result in dose exceeding the Dose Analysis of the Exclusion Area Boundary (EAB) and the Control Room, which is common to both Unit 1 and Unit 2. This condition may not be bounded by existing design and licensing documents; however, it poses no impact to the health and safety of the public or plant personnel. The Low Head Safety Injection relief valve has been isolated to prevent further leakage, and makeup to the RWST completed. At 1602 on November 2, 2019 the RWST was declared Operable. This event is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(ii)(B) and 10 CFR 50.72(b)(3)(v)(B), (C), (D) as an Unanalyzed Condition and a condition that could have prevented the Fulfillment of a Safety Function." The licensee notified the NRC resident inspector. | ||
ENS 56350 | 12 February 2023 13:00:00 | 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | Control Room Emergency Ventilation System Inoperable | The following information was provided by the licensee via phone call and email: At 0800 on February 12, 2023, it was discovered that both trains of control room emergency ventilation system were simultaneously inoperable due to a safety injection relief valve discharging to a Unit 1 sump. This leakage in conjunction with design basis loss of coolant accident may result in radiological dose exceeding limits to the exclusion area boundary and to the control room, which is common to both Unit 1 and Unit 2. Therefore, this condition is being reported as an eight-hour, nonemergency notification per 10 CFR 50.72(b)(3)(ii)(B) and 10 CFR 50.72(b)(3)(v)(D) as an 'Unanalyzed Condition and a Condition that Could Have Prevented Fulfillment of a Safety Function.' There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
Retraction of EN56350, Control Room Emergency Ventilation System Inoperable: Based on subsequent evaluation, it was determined that the control room emergency ventilation system remained operable due to the maximum measured leak rate being within the bounds of the analysis. The maximum measured leak rate of 32,594 cc/hr from the safety injection system did not challenge the calculated maximum engineered safety features leak rate of 45,600 cc/hr and remained within the current dose analysis limits. As such, this was not an unanalyzed condition and did not prevent the fulfillment of a safety function to mitigate the consequences of an accident. The NRC Resident Inspector has been notified. Notified R1DO (Bickett). | Control Room Emergency Ventilation | |
ENS 56569 | 11 June 2023 05:30:00 | 10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | Unanalyzed Condition | The following information was provided by the licensee via email: At 0130 EDT on June 11, 2023, it was discovered that the Beaver Valley Power Station, Unit No. 2 auxiliary building door A-35-5A, credited for tornado missile protection of the primary component cooling water system, was open and unlatched. Upon discovery, the door was shut and latched. This event is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(ii)(B) and 10 CFR 50.72(b)(3)(v)(B). There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. | ||
ENS 57115 | 9 May 2024 12:00:00 | 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Containment Bypass Condition Due to Degraded River Water Piping | The following information was provided by the licensee via phone and email: At 0800 EDT on May 9, 2024, it was identified during leak rate testing that through-wall flaws existed on reactor plant river water piping inside the containment building. This determination resulted in a containment bypass condition such that a gaseous release could have occurred at a location not analyzed for a release in the loss of coolant accident dose consequence analysis. This condition is not bounded by existing design and licensing documents. Evaluation of the condition of the piping is ongoing to support repair prior to startup. With the plant currently in cold shutdown, the containment, as specified in Technical Specification 3.6.1, is not required to be operable. There was no impact on the health and safety of the public or plant personnel. This event is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(ii)(A), 10 CFR 50.72(b)(3)(ii)(B), and 10 CFR 50.72(b)(3)(v)(C). The NRC Resident Inspector has been notified. |