04-13-2016 | On 02/13/2016 at 0206 ( CST) the plant was at 99 percent reactor power when Fuel Building Exhaust Fan "A" (1VFO4CA) tripped due to indicated high Secondary Containment (SC) vacuum during routine venting of the drywell per plant procedures. Following the fan trip, SC vacuum degraded, eventually exceeding the Technical Specification (TS) limit of 0.25 inch vacuum water gauge. The TS Limiting Condition for Operation (LCO) 3.6.4.1 Required Action A.1 and an Emergency Operating Procedure were entered. Plant Operations subsequently started the Standby Gas Treatment System (VG) and restored Secondary Containment within TS limits. An investigation determined that ice formed in the sensing line causing an inaccurate Secondary Containment vacuum reading on the indication and control loop for 1VFO4CA. This caused 1VFO4CA to trip which in turn led to a loss of Secondary Containment vacuum. A cause evaluation established that prior instrument sensing line designs did not recognize the potential to trap water in the sensing line to the Secondary Containment pressure instrumentation. Corrective actions will include completing an engineering change to install an alternate Fuel Building Ventilation ( VF) system sensing line design to prevent moisture accumulation line to ensure accurate indication and control of Secondary Containment pressure.
This event is reportable under 10 CFR 50.73(a)(2)(v)(C). |
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LER-2016-002, Trip of Fuel Building Ventilation Exhaust Fan Due to Moisture Formation Resulting In the Loss of Secondary Containment VacuumClinton Power Station, Unit 1 |
Event date: |
02-13-2016 |
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Report date: |
04-13-2016 |
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Reporting criterion: |
10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material |
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4612016002R00 - NRC Website |
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Category:Letter
MONTHYEARIR 05000461/20230042024-02-0202 February 2024 Integrated Inspection Report 05000461/2023004 ML23361A1572024-01-24024 January 2024 Audit Plan in Support of Review of License Amendment Request Regarding Revision of Technical Specifications Related to Reactor Water Cleanup Isolation ML24004A0792024-01-18018 January 2024 Exemption from Select Requirements of 10 CFR Part 73 (EPID L-2023-LLE-0041 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting)) IR 05000461/20234022023-12-27027 December 2023 Security Baseline Inspection Report 05000461/2023402 ML23305A1402023-12-13013 December 2023 Units 1 & 2; Nine Mile Point, Unit 2; Peach Bottom, Units 2 & 3; and Quad Cities, Units 1 and 2 - Issuance of Amendments to Adopt Traveler TSTF-580 IR 05000461/20235012023-12-0505 December 2023 Emergency Preparedness Biennial Exercise Inspection Report 05000461/2023501 ML23284A2512023-11-22022 November 2023 Amendment No. 250 to Adopt TSTF-332 ML23317A1192023-11-10010 November 2023 Constellation Energy Generation, LLC - 2023 Annual Report - Guarantees of Payment of Deferred Premiums IR 05000461/20230032023-11-0808 November 2023 Integrated Inspection Report 05000461/2023003 ML22300A2212023-11-0202 November 2023 Preliminary Decommissioning Cost Estimate and Fuel Management Plan RS-23-097, Constellation Energy Generation, LLC, Advisement of Leadership Changes and Submittal of Updated Standard Practice Procedures Plans2023-10-12012 October 2023 Constellation Energy Generation, LLC, Advisement of Leadership Changes and Submittal of Updated Standard Practice Procedures Plans IR 05000461/20233012023-09-12012 September 2023 NRC Initial License Examination Report 05000461/2023301 RS-23-090, Annual Report of Emergency Core Cooling System Evaluation Model Changes and Errors for Clinton Power Station2023-09-0707 September 2023 Annual Report of Emergency Core Cooling System Evaluation Model Changes and Errors for Clinton Power Station RS-23-080, Constellation Energy Generation, LLC, Application to Revise Technical Specifications to Adopt TSTF-264-A, Revision 0, 3.3.9 and 3.3.10 - Delete Flux Monitors Specific Overlap Requirement SRs2023-08-30030 August 2023 Constellation Energy Generation, LLC, Application to Revise Technical Specifications to Adopt TSTF-264-A, Revision 0, 3.3.9 and 3.3.10 - Delete Flux Monitors Specific Overlap Requirement SRs IR 05000461/20234202023-08-29029 August 2023 Security Baseline Inspection Report 05000461/2023420 RS-23-081, Request for License Amendment to Revise Technical Specifications Related to Reactor Water Cleanup Isolation Instrumentation2023-08-21021 August 2023 Request for License Amendment to Revise Technical Specifications Related to Reactor Water Cleanup Isolation Instrumentation IR 05000461/20230022023-08-0404 August 2023 Integrated Inspection Report 05000461/2023002 RS-23-085, Supplemental Information Related to Request for Partial Site Release2023-08-0303 August 2023 Supplemental Information Related to Request for Partial Site Release ML23209A8102023-07-28028 July 2023 05000461; Notification of an NRC Biennial Licensed Operator Requalification Program Inspection and Request for Information ML23198A0152023-07-27027 July 2023 License Renewal Application Public Meeting Summary of Pre-Submittal Meeting ML23202A0992023-07-24024 July 2023 Notification of NRC Baseline Inspection and Request for Information; Inspection Report 05000461/2023004 ML23200A2592023-07-24024 July 2023 June 27, 2023, Clinton Power Station License Renewal Environmental Pre-application Public Meeting-Meeting Summary IR 05000461/20234012023-07-19019 July 2023 Cyber Security Inspection Report 05000461/2023401 ML23194A1662023-07-19019 July 2023 Supplemental Information Needed for Acceptance of Requested Licensing Action Request for Partial Site Release ML23191A8772023-07-11011 July 2023 Operator Licensing Examination Approval Clinton Power Station July 2023 ML23178A2422023-06-28028 June 2023 Reassignment of the U.S. Nuclear Regulatory Commission Branch Chief in the Division of Operating Reactor Licensing for Plant Licensing Branch III RS-23-077, Response to NRC Regulatory Issue Summary 2023-01, Preparation and Scheduling of Operator Licensing Examinations2023-06-16016 June 2023 Response to NRC Regulatory Issue Summary 2023-01, Preparation and Scheduling of Operator Licensing Examinations RS-23-073, Request for Partial Site Release2023-06-0707 June 2023 Request for Partial Site Release IR 05000461/20230102023-05-26026 May 2023 Triennial Fire Protection Inspection Report 05000461/2023010 RS-23-042, Application to Revise Technical Specifications to Adopt TSTF-580, Provide Exception from Entering Mode 4 with No Operable RHR Shutdown Cooling2023-05-25025 May 2023 Application to Revise Technical Specifications to Adopt TSTF-580, Provide Exception from Entering Mode 4 with No Operable RHR Shutdown Cooling ML23143A3182023-05-23023 May 2023 Information Meeting (Open House) with a Question and Answer Session to Discuss NRC 2022 End-Of-Cycle Plant Performance Assessment of Clinton Power Station, Unit 1 IR 05000461/20230012023-05-0404 May 2023 Integrated Inspection Report 05000461/2023001 ML23118A3472023-05-0101 May 2023 County, 1 & 2; Nine Mile Point, 2; and Quad Cities, 1 & 2 - Correction of Amendment No. 193 Adoption of TSTF-306, Revision 2, Add Action to LCO 3.3.6.1 to Give Option to Isolate the Penetration EPID L-2022-LLA-0143 ML23114A2522023-04-28028 April 2023 Request to Use a Provision of a Later Edition of the ASME Boiler & Pressure Vessel Code, Section XI ML23081A0382023-04-25025 April 2023 County, 1 & 2; Nine Mile Point, 2; and Quad Cities, 1 & 2 - Issuance of Amendments to Adopt TSTF-306, Rev. 2, Add Action to LCO 3.3.6.1 to Give Option to Isolate the Penetration ML23110A3202023-04-21021 April 2023 Information Request to Support the NRC Annual Baseline Emergency Action Level and Emergency Plan Changes Inspection RS-23-049, Constellation Energy Generation, LLC, Report on Status of Decommissioning Funding for Reactors and Independent Spent Fuel Storage Installations2023-03-23023 March 2023 Constellation Energy Generation, LLC, Report on Status of Decommissioning Funding for Reactors and Independent Spent Fuel Storage Installations ML23061A1632023-03-0303 March 2023 Reassignment of the U.S. Nuclear Regulatory Commission Branch Chief in the Division of Operating Reactor Licensing for Plant Licensing Branch 3 IR 05000461/20220062023-03-0101 March 2023 Annual Assessment Letter for Clinton Power Station, Unit 1 (Report 05000461/2022006) RS-23-039, Request for License Amendment to Revise Technical Specifications Section 3.8.3, Diesel Fuel Oil, Lube Oil, and Starting Air2023-03-0101 March 2023 Request for License Amendment to Revise Technical Specifications Section 3.8.3, Diesel Fuel Oil, Lube Oil, and Starting Air ML23031A2972023-03-0101 March 2023 Issuance of Amendment No. 248 Adoption of TSTF-269, Revision 2 RS-23-045, Constellation Energy Generation, LLC Submittal of Fitness for Duty Performance Data Reports for 2022 Per 10 CFR 26.717(c) & 10 CFR 26.2032023-02-28028 February 2023 Constellation Energy Generation, LLC Submittal of Fitness for Duty Performance Data Reports for 2022 Per 10 CFR 26.717(c) & 10 CFR 26.203 ML23039A1852023-02-10010 February 2023 Integrated Inspection Report 05000461/2022004 07201046/2022001 RS-23-003, Constellation Energy Generation, LLC, Summary of Changes to Quality Assurance Topical Report, NO-AA-10, and Decommissioning Quality Assurance Program, NO-DC-102023-01-31031 January 2023 Constellation Energy Generation, LLC, Summary of Changes to Quality Assurance Topical Report, NO-AA-10, and Decommissioning Quality Assurance Program, NO-DC-10 IR 05000461/20220112023-01-27027 January 2023 Biennial Problem Identification and Resolution Inspection Report 05000461/2022011 RS-23-002, Application to Adopt TSTF-332, ECCS Response Time Testing2023-01-13013 January 2023 Application to Adopt TSTF-332, ECCS Response Time Testing ML23005A0682023-01-0505 January 2023 Notification of NRC Fire Protection Team Inspection Request for Information: Inspection Report 05000461/2023010 ML22341A6042022-12-0808 December 2022 Confirmation of Initial License Examination IR 05000461/20224022022-12-0606 December 2022 Security Baseline Inspection Report 05000461/2022402 RS-22-126, Constellation Energy Generation, LLC - Request to Use Provisions of a Later Edition of the ASME Boiler and Pressure Vessel Code, Section XI2022-11-30030 November 2022 Constellation Energy Generation, LLC - Request to Use Provisions of a Later Edition of the ASME Boiler and Pressure Vessel Code, Section XI 2024-02-02
[Table view] Category:Licensee Event Report (LER)
MONTHYEAR05000461/LER-2017-0102018-02-0505 February 2018 Division 1 Transformer Failure Leads to Instrument Air Isolation to Containment Requiring a Manual Reactor Scram, LER 17-010-00 for Clinton Power Station, Unit 1 Regarding Division 1 Transformer Failure Leads to Instrument Air Isolation to Containment Requiring a Manual Reactor Scram 05000461/LER-2017-0092018-01-0404 January 2018 Trip of Emergency Reserve Auxiliary Transformer Static VAR Compensator Causes Positive Secondary Containment Pressure Following Voltage Transient on 138 kV Offsite Source., LER 17-009-00 for Clinton, Unit 1, Regarding Trip of Emergency Reserve Auxiliary Transformer Static VAR Compensator Causes Positive Secondary Containment Pressure Following Voltage Transient on 138 kV Offsite Source 05000461/LER-2017-0052017-09-28028 September 2017 Automatic Reactor Scram During the Performance of Scram Time Testing As a Result of an Invalid Oscillation Power Range Monitor Growth Rate Trip, LER 17-005-01 for Clinton, Unit 1 Regarding Automatic Reactor Scram During the Performance of Scram Time Testing As a Result of an Invalid Oscillation Power Range Monitor Growth Rate Trip 05000461/LER-2017-0082017-08-11011 August 2017 Division 3 Shutdown Service Water Pump Start Failure, LER 17-008-00 for Clinton, Unit 1 re Division 3 Shutdown Service Water Pump Start Failure 05000461/LER-2017-0072017-08-0909 August 2017 Manual Reactor SCRAM due to Loss of Feedwater Heating, LER 17-007-00 for Clinton, Unit 1 re Manual Reactor SCRAM due to Loss of Feedwater Heating 05000461/LER-2017-0062017-08-0101 August 2017 1 OF 3, LER 17-006-00 for Clinton, Unit 1 re Secondary Containment Inoperable During Mode Change Due to Doors Propped Open 05000461/LER-2017-0042017-07-10010 July 2017 Main Steam Isolation Valve Local Leak Rate Test Limit Exceeded During Refueling Outage, LER 17-004-00 For Clinton Power Station, Unit 1 Re: Main Steam Isolation Valve Local Leak Rate Test Limit Exceeded During Refueling Outage 05000461/LER-2017-0022017-07-0505 July 2017 Failure of the Division 1 Diesel Generator Ventilation Fan Load Sequence Relay Circuit During Concurrent Maintenance of RHR Division 2 Results in an Unanalyzed Condition, LER 17-002-01 for Clinton, Unit 1, Regarding Failure of the Division 1 Diesel Generator Ventilation Fan Load Sequence Relay Circuit During Concurrent Maintenance of RHR Division 2 Results in an Unanalyzed Condition U-604357, Special Report: Inoperable Drywall High Range Gamma Radiation Monitor2017-07-0505 July 2017 Special Report: Inoperable Drywall High Range Gamma Radiation Monitor 05000461/LER-2017-0032017-07-0303 July 2017 Implementation of Enforcement Guidance Memorandum (EGM) 11 - 003, Revision 3, LER 17-003-00 for Clinton Power Station, Unit 1 Regarding Implementation of Enforcement Guidance Memorandum (EGM) 11-003, Revision 3 05000461/LER-2017-0012017-04-21021 April 2017 Failure of the 138 kV Offsite Power Source Results in a Loss of Secondary Containment Vacuum, LER 17-001-00 for Clinton, Unit 1, Regarding Failure of the 138 kV Offsite Power Source Results in a Loss of Secondary Containment Vacuum 05000461/LER-2016-0102017-03-0606 March 2017 1 OF 3, LER 16-010-01 for Clinton Power Station, Unit 1 RE: Failure to Complete Technical Specification Required Actions within the Completion Time Resulted in a Condition Prohibited by Technical Specifications 05000461/LER-2016-0092016-08-22022 August 2016 Trip of Fuel Building Fans Due to Damper Failure Results in Loss of Secondary Containment, LER 16-009-00 for Clinton Power Station, Unit 1 Regarding Trip of Fuel Building Fans Due to Damper Failure Results in Loss of Secondary Containment 05000461/LER-2016-0072016-07-15015 July 2016 Main Steam Line Flexible Hose Intergranular Stress Corrosion Cracking Identified During Refueling Outage, LER 16-007-00 for Clinton Power Station, Unit 1, Regarding Main Steam Line Flexible Hose lntergranular Stress Corrosion Cracking Identified During Refueling Outage 05000461/LER-2016-0082016-07-15015 July 2016 Implementation of Enforcement Guidance Memorandum (EGM) 11-003, Revision 3, LER 16-008-00 for Clinton Power Station, Unit 1, Regarding Implementation of Enforcement Guidance Memorandum (EGM) 11-003, Revision 3 05000461/LER-2016-0062016-06-10010 June 2016 Missed Surveillance Results in a Condition Prohibited by Technical Specifications, LER 16-006-00 for Clinton Power Station Unit 1 RE: Missed Surveillance Results in a Condition Prohibited by Technical Specifications 05000461/LER-2016-0052016-05-31031 May 2016 Insulator Failure On the Reserve Auxiliary Transformer Results In A Loss of Secondary Containment Vacuum, LER 16-005-00 for Clinton Power Station, Unit 1, Regarding Insulator Failure on the Reserve Auxiliary Transformer Results in a Loss of Secondary Containment Vacuum 05000461/LER-2016-0042016-05-26026 May 2016 Trip of Emergency Reserve Auxiliary Transformer Static VAR Compensator Causes Positive Secondary Containment Pressure Following Lightning Strike on 138 kV Offsite Source, LER 16-004-00 for Clinton, Unit 1, Regarding Trip of Emergency Reserve Auxiliary Transformer Static VAR Compensator Causes Positive Secondary Containment Pressure Following Lightning Strike on 138 kV Offsite Source 05000461/LER-2016-0032016-05-23023 May 2016 Bypassing Both Divisions of Reactor Water Cleanup Leak Detection System is a Reportable Loss of Safety Function, LER 16-003-00 for Clinton Power Station, Unit 1 Regarding Bypassing Both Divisions of Reactor Water Cleanup Leak Detection System is a Reportable Loss of Safety Function 05000461/LER-2016-0022016-04-13013 April 2016 Trip of Fuel Building Ventilation Exhaust Fan Due to Moisture Formation Resulting In the Loss of Secondary Containment Vacuum, LER 16-002-00 for Clinton, Unit 1, Regarding Trip of Fuel Building Ventilation Exhaust Fan Due to Moisture Formation Resulting In the Loss of Secondary Containment Vacuum 2018-02-05
[Table view] |
Reported lessons learned are incorporated into the licensing process and fed back to industry.
Send comments regarding burden estimate to the FOIA, Privacy and Information Collections Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to Infocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required.to respond to, the information collection.
PLANT AND SYSTEM IDENTIFICATION
General Electric—Boiling Water Reactor, 3473 Megawatts Thermal Rated Core Power Energy Industry Identification System (EIIS) codes are identified in .the text as [XX]
EVENT IDENTIFICATION
Trip of Fuel Building Ventilation Exhaust Fan Due to Moisture Formation Resulting In the Loss of Secondary Containment Vacuum A. Plant Operating Conditions before the Event Unit: 1 Event Date: 2/13/16 Mode: 1 Mode Name: Power Operation
B. DESCRIPTION OF EVENT
Event Time: 0206 Reactor Power: 99 percent On February 13, 2016 at 0206, during routine venting of the drywell, the main control room (MCR) received a fuel building ventilation (VF) system alarm. At 0208 Fuel Building exhaust fan 1VFO4CA tripped and 'B' exhaust fan 1VFO4CB auto started, however, secondary containment vacuum continued to degrade. Secondary Containment was declared inoperable when the vacuum degraded to less than 0.25 inch water gauge (WG). TS LCO 3.6.4.1 "Secondary Containment", Required Action A.1 was entered. When Secondary Containment differential pressure value became greater than 0 inch of vacuum WG with 1VFO4CB fan operating, procedure EOP-8, Secondary 'Containment Control, was entered.
At 0212, Secondary Containment vacuum was at 0.15 inch WG with 1VFO4CB running and 1VFO4CA in standby. With Secondary Containment vacuum still outside TS limits, the MCR secured the VF exhaust fans at 0255 per CPS 3404.01, Fuel Building HVAC (VF). At 0256 Standby Gas Treatment System (VG) Train A was started per CPS 3319.01, Standby Gas Treatment (VG).
Secondary Containment vacuum was restored to greater than 0.25 inch WG at 0257 and Secondary Containment was declared operable. TS LCO 3.6.4.1 Required Action A.1 and EOP-8 were exited.
A troubleshooting team determined that ice had formed resulting in a blockage in the low side sensing line to the environment as the most probable cause of the event. Other locations for sensing line clogging were also investigated.
After disassembling, thawing, and cleaning the intake tubing, technicians performed a blowdown of the instrumentation tubing. Following the blowdown, Operations successfully restarted VF exhaust fan 1VFO4CA. Secondary Containment vacuum was restored to normal.
Clinton Power Station, Unit 1 05000461 The event described in this LER was documented in Event Notification No. 51732 which was provided to the NRC on February 13, 2016 at 0909.
C. CAUSE OF EVENT
An investigation identified that ice formed in the low side of the VF 'A' sensing line causing an inaccurate Secondary Containment vacuum reading on both indication and control loop for the 1VFO4CA. This caused 1VFO4CA to trip which in turn led to a loss of Secondary Containment vacuum. Moisture had collected in the sensing line and froze due to externally cold weather conditions. At the time of the event, the outside air temperature was 8 degrees Fahrenheit. A subsequent causal evaluation established that prior instrument sensing line designs did not recognize the potential to trap water in the sensing line as the cause of this event.
D. SAFETY ANALYSIS
This event is reportable in accordance with 10CFR50 50.73(a)(2)(v)(C) as a condition that could have prevented fulfillment of a safety function to control the release of radioactive material because secondary containment was declared inoperable.
The VG system was fully operable at the time of the event and capable of performing the required safety function. Operations entered EOP-8 for Secondary Containment vacuum less than minus 0.25 inch water gauge and entered TS LCO 3.6.4.1, Required Action A.1.
Secondary containment vacuum was restored to within TS limits within the completion time requirement. The secondary containment vacuum is kept slightly negative relative to the atmospheric pressure to prevent leakage to the atmosphere. The VF system is anon-safety ventilation system which is normally in service to maintain secondary containment vacuum. The VG System is the safety-related system which is relied upon to perform this function following an accident. During the event the VG system was placed in service and restored Secondary Condition to operability consistent with its safety function. Therefore, the ability of the station to maintain secondary containment in an accident scenario was never jeopardized or challenged by the VF system fan trip.
E. CORRECTIVE ACTIONS
Technicians disassembled, thawed, and cleaned the intake tubing. Afterwards, they performed a blowdown of the instrumentation tubing. Following this activity, Operations successfully restarted the VF fan. Interim measures to prevent a recurrence of icing included the installation of heat tape inside the sensing line and a heat source (light bulb) inside the protective housing.
An Engineering Change (EC) will be completed to install an alternate VF sensing line design to prevent moisture accumulation in the instrument sensing line and ensure accurate indication and control of the Secondary Containment pressure. A subsequent review of VF performance will be conducted to ensure the modification effectively prevented moisture accumulation.
F. PREVIOUS SIMILAR OCCURENCES
A review for previous occurrences did not identify a similar licensee event report at CPS.
CPS Issue Report (IR) 2613542 identified a similar condition on January 17, 2016 in which VF Ventilation System exhaust fans repeatedly tripped on low Fuel Building vacuum. The VG System was started to maintain secondary containment vacuum. However, in this case, Secondary Containment vacuum was maintained greater than minus 0.25 inch WG, and therefore not reportable.
VF vacuum (Computer point VF-BA201) and Containment Building (VR) vacuum (Computer point VR-BA201) were reading outside their normal operating bands. The apparent cause of the VF exhaust fans tripping was due to blockage/moisture in the vacuum sensing line. This was confirmed when the sensing line was blown down to restore the indicated VF vacuum to normal operating band.
Corrective actions resulting from this event included scheduling a blowdown of the instrument sensing line during the upcoming refueling outage and evaluating long term plans to resolve this recurring condition.
This occurrence is directly applicable to the conditions noted in this LER and documents a prior occurrence of the same failure mode earlier in 2016.
G. COMPONENT FAILURE DATA
There were no component failures associated with this event.
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05000461/LER-2016-010 | 1 OF 3 LER 16-010-01 for Clinton Power Station, Unit 1 RE: Failure to Complete Technical Specification Required Actions within the Completion Time Resulted in a Condition Prohibited by Technical Specifications | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000461/LER-2016-011 | Incorrect Calculation Method Used to Demonstrate Control Room Habitability | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition | 05000461/LER-2016-001 | 1 OF 4 | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | 05000461/LER-2016-012 | 1 OF 4 | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000461/LER-2016-002 | Trip of Fuel Building Ventilation Exhaust Fan Due to Moisture Formation Resulting In the Loss of Secondary Containment Vacuum LER 16-002-00 for Clinton, Unit 1, Regarding Trip of Fuel Building Ventilation Exhaust Fan Due to Moisture Formation Resulting In the Loss of Secondary Containment Vacuum | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000461/LER-2016-003 | Bypassing Both Divisions of Reactor Water Cleanup Leak Detection System is a Reportable Loss of Safety Function LER 16-003-00 for Clinton Power Station, Unit 1 Regarding Bypassing Both Divisions of Reactor Water Cleanup Leak Detection System is a Reportable Loss of Safety Function | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000461/LER-2016-004 | Trip of Emergency Reserve Auxiliary Transformer Static VAR Compensator Causes Positive Secondary Containment Pressure Following Lightning Strike on 138 kV Offsite Source LER 16-004-00 for Clinton, Unit 1, Regarding Trip of Emergency Reserve Auxiliary Transformer Static VAR Compensator Causes Positive Secondary Containment Pressure Following Lightning Strike on 138 kV Offsite Source | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000461/LER-2016-005 | Insulator Failure On the Reserve Auxiliary Transformer Results In A Loss of Secondary Containment Vacuum LER 16-005-00 for Clinton Power Station, Unit 1, Regarding Insulator Failure on the Reserve Auxiliary Transformer Results in a Loss of Secondary Containment Vacuum | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000461/LER-2016-006 | Missed Surveillance Results in a Condition Prohibited by Technical Specifications LER 16-006-00 for Clinton Power Station Unit 1 RE: Missed Surveillance Results in a Condition Prohibited by Technical Specifications | | 05000461/LER-2016-007 | Main Steam Line Flexible Hose Intergranular Stress Corrosion Cracking Identified During Refueling Outage LER 16-007-00 for Clinton Power Station, Unit 1, Regarding Main Steam Line Flexible Hose lntergranular Stress Corrosion Cracking Identified During Refueling Outage | 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded | 05000461/LER-2016-008 | Implementation of Enforcement Guidance Memorandum (EGM) 11-003, Revision 3 LER 16-008-00 for Clinton Power Station, Unit 1, Regarding Implementation of Enforcement Guidance Memorandum (EGM) 11-003, Revision 3 | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000461/LER-2016-009 | Trip of Fuel Building Fans Due to Damper Failure Results in Loss of Secondary Containment LER 16-009-00 for Clinton Power Station, Unit 1 Regarding Trip of Fuel Building Fans Due to Damper Failure Results in Loss of Secondary Containment | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material |
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