On October 6, 2017 at 1945 hours0.0225 days <br />0.54 hours <br />0.00322 weeks <br />7.400725e-4 months <br />, a loss of Control Room Habitability Envelope (CRHE) was declared due to failing to meet Technical Specification (TS) 3.7.3, Surveillance Requirement (SR) 3.7.3.4 during surveillance testing. The CRHE is required to be maintained such that occupants can control the reactor safely under normal conditions and maintain it in a safe condition following a radiological event, hazardous chemical release, or a smoke challenge. Mitigating actions were identified and include the ability to issue potassium iodide (KI) to the control room staff and Emergency Plan responders. With implementation of the mitigating actions, the dose consequence to the control room operators and affected Emergency Plan personnel is substantially less than the regulatory limit of 5 Rem Total Effective Dose Equivalent ( TEDE) for event duration.
On October 6, 2017, at 2146 hours0.0248 days <br />0.596 hours <br />0.00355 weeks <br />8.16553e-4 months <br />, this condition was reported (ENS #53003) in accordance with 10 CFR 50.72(b)(3)(v)(D) and is also reportable in accordance with the corresponding criteria of 10 CFR 50.73(a)(2)(v)(D). Additional review resulted in an assumption that the gasket could have been out of position since installation in 2012; therefore, this condition is also being reported in accordance with 10 CFR 50.73(a)(2)(i)(B) as a condition prohibited by Technical Specifications.
The cause was out of position door gaskets on the "A" Control Room Emergency Outside Air Supply (CREOAS) filter train due to inadequate installation. Corrective actions include repairing the door gaskets, performing a successful retest, and adding a step in the preventive maintenance activity when replacing the door gaskets to ensure the gasket is entirely glued into the channel such that the gasket is in contact with the entire channel.
There were no actual consequences to the health and safety of the public as a result of this event. |
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Category:Letter
MONTHYEARML24249A1362024-09-0404 September 2024 EN 57304 - Westinghouse Electric Company, LLC, Final Report - No Embedded Files. Notification of the Potential Existence of Defects Pursuant to 10 CFR Part 21 ML24233A2192024-09-0303 September 2024 – Authorized Alternative to Requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code IR 05000387/20240052024-08-29029 August 2024 Updated Inspection Plan for Susquehanna Steam Electric Station, Units 1 and 2 (Report 05000387/2024005 and 05000388/2024005) IR 05000387/20240022024-08-12012 August 2024 Integrated Inspection Report 05000387/2024002 and 05000388/2024002 ML24208A0962024-07-25025 July 2024 57243-EN 57243 - Rssc Wire & Cable LLC, Dba Marmon - Part 21 Notification PLA-8117, 23rd Refueling Outage Owners Activity Report (PLA-8117)2024-07-23023 July 2024 23rd Refueling Outage Owners Activity Report (PLA-8117) ML24197A0982024-07-15015 July 2024 Request for Information for a Biennial Problem Identification and Resolution Inspection; Inspection Report 05000387/2024010 and 05000388/2024010 ML24127A2262024-05-29029 May 2024 Issuance of Amendment Nos. 288 and 272 Adoption of TSTF-563 PLA-8126, Response to Request for Confirmation of Information Regarding Relief Request 1RR062024-05-29029 May 2024 Response to Request for Confirmation of Information Regarding Relief Request 1RR06 PLA-8122, Annual Radiological Environmental Operating Report (PLA-8122)2024-05-28028 May 2024 Annual Radiological Environmental Operating Report (PLA-8122) PLA-8115, Relief Request IRR06 One Time Extension to the Fourth 10-Year Inservice Testing Program Interval (PLA-8115)2024-05-23023 May 2024 Relief Request IRR06 One Time Extension to the Fourth 10-Year Inservice Testing Program Interval (PLA-8115) IR 05000387/20240012024-05-13013 May 2024 Integrated Inspection Report 05000387/2024001 and 05000388/2024001 IR 05000387/20244042024-05-0707 May 2024 Information Request for the Cybersecurity Baseline Inspection, Notification to Perform Inspection 05000387/2024404 and 05000388/2024404 ML24082A1372024-04-22022 April 2024 Issuance of Amendment Nos. 287 and 271 Adoption of TSTF-568, Revision 2 and Associated Technical Specification Changes PLA-8101, Re 2023 Annual Report of Radiation Exposure2024-04-22022 April 2024 Re 2023 Annual Report of Radiation Exposure PLA-8094, Radioactive Effluent Release Report and Offsite Dose Calculation Manual PLA-80942024-04-22022 April 2024 Radioactive Effluent Release Report and Offsite Dose Calculation Manual PLA-8094 PLA-8095, 2023 Annual Radiological Environmental Operating Report (PLA-8095)2024-04-22022 April 2024 2023 Annual Radiological Environmental Operating Report (PLA-8095) PLA-8102, Annual Environmental Operating Report (Nonradiological) PLA-81022024-04-11011 April 2024 Annual Environmental Operating Report (Nonradiological) PLA-8102 PLA-8113, Response to Request for Additional Information Regarding Relief Request 4RR-11 (PLA-8113)2024-04-11011 April 2024 Response to Request for Additional Information Regarding Relief Request 4RR-11 (PLA-8113) PLA-8112, Relief Request 4RR-11 Relief from End of Interval Boundary Leakage Test PLA-81122024-04-0909 April 2024 Relief Request 4RR-11 Relief from End of Interval Boundary Leakage Test PLA-8112 PLA-8110, Submittal of Unit 1 Cycle 24 Core Operating License Report (Pla 8110)2024-04-0404 April 2024 Submittal of Unit 1 Cycle 24 Core Operating License Report (Pla 8110) ML24092A4022024-04-0101 April 2024 Annual Financial Report (PLA-8098) PLA-8100, Property Insurance Program (PLA-8100)2024-04-0101 April 2024 Property Insurance Program (PLA-8100) PLA-8109, Supplement to Request for Exemption from Certain Requirements of 10 CR 72.212 and 10 CFR 72.214 Resulting from Fuel Basket Design Control Compliance (PLA-8109)2024-03-21021 March 2024 Supplement to Request for Exemption from Certain Requirements of 10 CR 72.212 and 10 CFR 72.214 Resulting from Fuel Basket Design Control Compliance (PLA-8109) ML24067A2512024-03-19019 March 2024 Authorized Alternative to Requirements of the ASME Code PLA-8107, Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214 Resulting from Fuel Basket Design Control Compliance2024-03-19019 March 2024 Request for Exemption from Certain Requirements of 10 CFR 72.212 and 10 CFR 72.214 Resulting from Fuel Basket Design Control Compliance ML24044A2532024-03-14014 March 2024 Associated Independent Spent Fuel Storage Installation – Exemption from Select Requirements of 10 CFR Part 73 (EPID L-2023-LLE-0077 (Security Notifications, Reports, and Recordkeeping & Suspicious Activity Reporting)) IR 05000387/20240112024-02-29029 February 2024 Commercial Grade Dedication Inspection Report 05000387/2024011 and 05000388/2024011 IR 05000387/20230062024-02-28028 February 2024 Annual Assessment Letter for Susquehanna Steam Electric Station, Units 1 and 2 (Reports 05000387/2023006 and 05000388/2023006) ML24039A1882024-02-27027 February 2024 Issuance of Amendment Nos. 286 and 270 Changes to Technical Specifications for Control Rods ML24037A3072024-02-22022 February 2024 Summary of Regulatory Audit in Support of Relief Request 5RR-02 PLA-8099, Proof of Financial Protection and Guarantee of Payment of Deferred Premiums (PLA-8099)2024-02-13013 February 2024 Proof of Financial Protection and Guarantee of Payment of Deferred Premiums (PLA-8099) IR 05000387/20230042024-02-0707 February 2024 Integrated Inspection Report 05000387/2023004 and 05000388/2023004 PLA-8096, Response to Request for Additional Information Regarding Proposed Relief Request for the Fifth 10-Year Inservice Test Program Interval2024-01-0404 January 2024 Response to Request for Additional Information Regarding Proposed Relief Request for the Fifth 10-Year Inservice Test Program Interval PLA-8077, Emergency Plan Revision 67 (PLA-8077)2023-12-27027 December 2023 Emergency Plan Revision 67 (PLA-8077) IR 05000387/20230102023-12-11011 December 2023 Fire Protection Team Inspection Report 05000387/2023010 and 05000388/2023010 PLA-8089, Submittal of Revision to Inservice Testing Program Plan2023-12-0505 December 2023 Submittal of Revision to Inservice Testing Program Plan PLA-8084, Application to Revise Technical Specifications to Adopt TSTF-568, Revise Applicability of BWR TS 3.6.2.5 and TS 3.6.3.22023-11-29029 November 2023 Application to Revise Technical Specifications to Adopt TSTF-568, Revise Applicability of BWR TS 3.6.2.5 and TS 3.6.3.2 ML23345A0682023-11-28028 November 2023 Technical Specification Bases, Manual PLA-8091, Response to Request for Additional Information Regarding Proposed Relief Request for the Fifth 10-Year Inseervice Inspection Interval (PLA-8091)2023-11-0808 November 2023 Response to Request for Additional Information Regarding Proposed Relief Request for the Fifth 10-Year Inseervice Inspection Interval (PLA-8091) IR 05000387/20230032023-11-0303 November 2023 Integrated Inspection Report 05000387/2023003 and 05000388/2023003 PLA-8082, Proposed Amendment to Licenses NPF-14 and NPF-22: Application to Revise Technical Specifications to Adopt TSTF-563, Revise Instrument Testing Definitions to Incorporate the Surveillance Frequency Control Program2023-11-0202 November 2023 Proposed Amendment to Licenses NPF-14 and NPF-22: Application to Revise Technical Specifications to Adopt TSTF-563, Revise Instrument Testing Definitions to Incorporate the Surveillance Frequency Control Program ML23291A1132023-10-12012 October 2023 Submittal of Revision 71 to Updated Final Safety Analysis Report and Revision 25 to Fire Protection Review Report ML23279A0612023-10-0505 October 2023 Paragon Energy Solutions LLC, Part 21 Final Report Re Potential Defect with Eaton Jd and Hjd Series Molded Case Circuit Breakers (Mccbs) ML23277A0412023-10-0505 October 2023 Notification of Commercial Grade Dedication Inspection (05000387/2024011 and 05000388/2024011) and Request for Information IR 05000387/20233012023-09-20020 September 2023 Initial Operator Licensing Examination Report 05000387/2023301 and 05000388/2023301 ML23254A0242023-09-0606 September 2023 Paragon Energy Solutions LLC, Potential Defect with Eaton Jd and Hjd Series Molded Case Circuit Breakers (Mccbs) IR 05000387/20230052023-08-31031 August 2023 Updated Inspection Plan for Susquehanna Steam Electric Station, Units 1 and 2 (Report 05000387/2023005 and 05000388/2023005) ML23228A1952023-08-21021 August 2023 Summary of August 10, 2023, Public Observation Meeting Re. Proposed Alternative PLA-8080, Proposed Relief for Valve 251130 (PLA-8080)2023-08-14014 August 2023 Proposed Relief for Valve 251130 (PLA-8080) 2024-09-04
[Table view] Category:Licensee Event Report (LER)
MONTHYEAR05000388/LER-2017-0102018-02-0202 February 2018 Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switches, LER 17-010-00 for Susquehanna, Unit 2 Regarding Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switches 05000387/LER-2017-0072017-10-0909 October 2017 Secondary Containment Declared Inoperable Due to the opening of a plenum., LER 17-007-00 for Susquehanna Steam Electric Station Regarding Secondary Containment Declared Inoperable Due to Supply Air Flow 05000387/LER-2017-0052017-10-0404 October 2017 Automatic Reactor Protection System Trip on High Neutron Flux, LER 17-005-01 for Susquehanna, Unit 1 Regarding Automatic Reactor Protection System Trip on High Neutron Flux 05000388/LER-2017-0082017-09-18018 September 2017 1 OF 3, LER 17-008-00 for Susquehanna, Unit 2, Regarding Condition Prohibited by Technical Specifications Due to a Loose Terminal Block Associated with a Primary Containment Isolation Valve 05000387/LER-2017-0062017-09-0606 September 2017 Control Room Envelope In-leakage Exceeded the Technical Specification Limit, LER 17-006-00 for Susquehanna, Unit 2, Regarding Secondary Containment Declared Inoperable Due to Trip of Zone II Exhaust Fan 05000387/LER-2017-0042017-08-0404 August 2017 Secondary Containment Declared Inoperable Due to Failure of an Exhaust Fan Breaker., LER 17-004-00 for Susquehanna, Unit 1, Regarding Secondary Containment Declared Inoperable Due to Failure of an Exhaust Fan Breaker 05000388/LER-2017-0022017-05-0505 May 2017 Implementation of Enforcement Guidance Memorandum (EGM) 11-003, Revision 3 during Unit 2 Refueling, LER 17-002-00 for Susquehanna, Unit 2, Regarding Implementation of Enforcement Guidance Memorandum (EGM) 11-003, Revision 3 During Unit 2 Refueling 05000387/LER-2017-0032017-05-0505 May 2017 Susquehanna Steam Electric Station Unit 1 05000387, LER 17-003-00 for Susquehanna, Units 1 and 2, Regarding Loss of Secondary Containment Zone 3 Due to Fan Trip 05000387/LER-2017-0012017-05-0505 May 2017 Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors, LER 17-001-00 for Susquehanna, Unit 2, Regarding Secondary Containment Declared Inoperable Due to Airlock Doors Open Due to Sticking Door Latch 05000387/LER-2017-0022017-04-12012 April 2017 Secondary Containment Breach due to Simultaneous Opening of Airlock Doors, LER 17-002-00 for Susquehanna, Unit 1, Regarding Secondary Containment Breach due to Simultaneous Opening of Airlock Doors 05000388/LER-2016-0052016-07-12012 July 2016 Unit 2 HPCI Manually Overridden Prior to a Manual Scram During a Plant Transient, LER 16-005-00 for Susquehanna, Unit 2, Regarding HPCI Manually Overridden Prior to a Manual Scram During a Plant Transient 05000387/LER-2016-0152016-06-15015 June 2016 Secondary Containment Declared Inoperable Due to Airlock Doors Open Due to a Human Performance Error, LER 16-015-00 for Susquehanna, Unit 1, Regarding Secondary Containment Declared Inoperable Due to Airlock Doors Open Due to a Human Performance Error 05000387/LER-2016-0142016-06-0909 June 2016 Secondary Containment Declared Inoperable Due to Airlock Doors Open Due to a Human Performance Error, LER 16-014-00 for Susquehanna, Unit 1, Regarding Secondary Containment Declared Inoperable Due to Airlock Doors Open Due to a Human Performance Error 05000387/LER-2016-0132016-06-0909 June 2016 Secondary Containment Declared Inoperable Due to Simultaneous Opening of Double Airlock Doors, LER 16-013-00 for Susquehanna, Unit 1, Regarding Secondary Containment Declared Inoperable Due to Simultaneous Opening of Double Airlock Doors 05000387/LER-2016-0102016-05-31031 May 2016 Secondary Containment Declared Inoperable Due to Airlock Doors Open Due to Medical Emergency, LER 16-010-00 for Susquehanna, Unit 1, Regarding Secondary Containment Declared Inoperable Due to Airlock Doors Open Due to Medical Emergency 05000387/LER-2016-0092016-05-26026 May 2016 Valid Primary Containment Isolation Actuation during Local Leak Rate Testing due to Human Performance Error, LER 16-009-00 for Susquehanna, Unit 1, Regarding Valid Primary Containment Isolation Actuation During Local Leak Rate Testing Due to Human Performance Error 05000387/LER-2016-0082016-05-19019 May 2016 Inoperability of Diesel Generator Due to Misalignment of MOC Switch Contacts Due to Inadequate Post Maintenance Testing, LER 16-008-00 for Susquehanna, Unit 1, Regarding Inoperability of Diesel Generator Due to Misalignment of MOC Switch Contacts Due to Inadequate Post Maintenance Testing 05000387/LER-2016-0112016-05-16016 May 2016 Valve inoperability for a period longer than allowed by Technical Specifications, LER 16-011-00 for Susquehanna, Unit 1, Regarding Valve Inoperability for a Period Longer Than Allowed by Technical Specifications 05000387/LER-2016-0052016-05-16016 May 2016 Secondary Containment Declared Inoperable Due to Airlock Doors Open Due to Human Performance Error, LER 16-005-00 for Susquehanna, Units 1 and 2, Regarding Secondary Containment Declared Inoperable Due to Airlock Doors Open Due to Human Performance Error 05000387/LER-2016-0062016-05-10010 May 2016 Implementation of Enforcement Guidance Memorandum (EGM) 11-003, Revision 3, LER 16-006-00 for Susquehanna, Unit 1, Regarding Implementation of Enforcement Guidance Memorandum (EGM) 11-003, Revision 3 05000387/LER-2016-0042016-05-10010 May 2016 Momentary Loss of Secondary Containment due to Both Airlock Doors on Elevation 779 of the Unit 2 Reactor Building being Opened at the Same Time, LER 16-004-00 for Susquehanna, Unit 1, Regarding Momentary Loss of Secondary Containment Due to Both Airlock Doors on Elevation 779 of the Unit 2 Reactor Building Being Opened at the Same Time 05000387/LER-2016-0032016-05-0606 May 2016 Unit 2 Zone 3 HVAC unable to maintain Zone 3 differential pressure greater than 0.25 in wg, LER 16-003-00 for Susquehanna, Unit 1, Regarding Unit 2 Zone 3 HVAC Unable to Maintain Zone 3 Differential Pressure Greater Than 0.25 in wg 05000387/LER-2016-0072016-05-0303 May 2016 Inoperability of Swing Bus Transfer Switch Due to Deformed Bolt on Linkage, LER 16-007-00 for Susquehanna, Unit 1, Regarding Inoperability of Swing Bus Transfer Switch Due to Deformed Bolt on Linkage 05000387/LER-2016-0012016-04-18018 April 2016 Secondary Containment Declared Inoperable Due to an Airlock Doors Open Due to Random Occurrence, LER 16-001-00 for Susquehanna, Unit 1, Regarding Secondary Containment Declared Inoperable Due to an Airlock Doors Open Due to Random Occurrence 05000387/LER-2016-0022016-04-18018 April 2016 Secondary Containment Declared Inoperable Due to an Airlock Doors Open Due to Random Occurrence, LER 16-002-00 for Susquehanna, Unit 1, Regarding Secondary Containment Declared Inoperable Due to an Airlock Doors Open Due to Random Occurrence 05000387/LER-2015-0062016-03-30030 March 2016 Loss of Safety Function due to Inoperability of Both Trains of the Standby Gas Treatment System and a Loss of Safety Function of the Control Room Emergency Outside Air Supply System due to Air Flow Controller found in Manual, LER 15-006-01 for Susquehanna, Unit 1, Regarding Loss of Safety Function due to Inoperability of Both Trains of the Standby Gas Treatment System and a Loss of Safety Function of the Control Room Emergency Outside Air Supply System due to Air Flow... 05000387/LER-2015-0012016-02-10010 February 2016 Inoperability of the 'B' Emergency Diesel Generator due to Fuel Oil Leakage, LER 15-001-01 for Susquehanna, Unit 1, Regarding Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Steam Dome - Low Switches 05000387/LER-2015-0032016-01-26026 January 2016 Secondary Containment Inoperability Due to Failure to Meet Technical Specification Surveillance Requirement 3.6.4.1.1, LER 15-003-01 for Susquehanna, Unit 1, Regarding Secondary Containment Inoperability Due to Failure to Meet Technical Specification Surveillance Requirement 3.6.4.1.1 05000387/LER-2015-0092016-01-11011 January 2016 Pressure Boundary Leakage From an Inadequate Weld Repair in Small Bore Pump Seal Vent Piping, LER 15-009-00 for Susquehanna, Unit 1, Regarding Pressure Boundary Leakage From an Inadequate Weld Repair in Small Bore Pump Seal Vent Piping 05000387/LER-2015-0072016-01-0808 January 2016 Unit 1 'B' Inboard Main Steam Isolation Valve, HV141F022B closed during surveillance test which caused a SCRAM on Unit 1, LER 15-007-00 for Susquehanna, Unit 1, Regarding 'B' Inboard Main Steam Isolation Valve, HV141 F022B Closed During Surveillance Test Which Caused a SCRAM PLA-7323, LER 015-001-00 for Susquehanna Regarding Inoperability of the B Emergency Diesel Generator Due to Fuel Oil Leakage2015-04-28028 April 2015 LER 015-001-00 for Susquehanna Regarding Inoperability of the B Emergency Diesel Generator Due to Fuel Oil Leakage 2018-02-02
[Table view] |
comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to 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.
CONDITIONS PRIOR TO EVENT
Unit 1 — Mode 1, approximately 100 percent Rated Thermal Power Unit 2 — Mode 1, approximately 100 percent Rated Thermal Power
EVENT DESCRIPTION
On October 6, 2017 at 1945 hours0.0225 days <br />0.54 hours <br />0.00322 weeks <br />7.400725e-4 months <br />, a loss of Control Room Habitability Envelope (CRHE) [EllS System Identifier: NA] was declared due to failing to meet Technical Specification (TS) 3.7.3, Surveillance Requirement (SR) 3.7.3.4 during surveillance testing. Specifically, during testing of the "A" Control Room Emergency Outside Air Supply (CREOAS) train [EIIS System Identifier: VI], the unfiltered inleakage was determined to be 222 cubic feet per minute (cfm) plus a test uncertainty of 458 cfm for a total of 680 cfm.
This value exceeded the allowable inleakage value of 500 cfm. The CRHE is required to be maintained such that occupants can control the reactor safely under normal conditions and maintain it in a safe condition following a radiological event, hazardous chemical release, or a smoke challenge. Technical Specification (TS) 3.7.3, Required Action B.1, required immediate initiation of action to implement mitigating actions. The mitigating actions included the ability to issue potassium iodide (KI) to the control room staff and Emergency Plan responders. An adequate supply was verified to be available. Required Action B.2 required that, within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, the mitigating actions be verified to ensure CRE occupant exposures to radiological, chemical, and smoke hazards will not exceed limits. Toxic chemical analysis and smoke infiltration analysis assume normal ventilation operation and are not invalidated by the failed SR 3.7.3.4 results for the CRE. Analyses of dose impact determined that, with issuance of KI in accordance with procedures and an unfiltered inleakage of 800 cfm, the dose consequence to the control room operators and affected Emergency Plan personnel is substantially less than the regulatory limit of 5 Rem Total Effective Dose Equivalent (TEDE) for event duration.
Smoke testing was completed to identify sources of leakage. Leakage was identified from the filter train and fan plenum doors of the "A" CREOAS filter train. The door gaskets were found to be out of position.
The gaskets had been replaced in 2012 and 2013 (between November 26, 2012 and November 27, 2013) as part of a preventive maintenance activity. The gaskets on the filter train and the fan plenum door were repaired.
On November 30, 2017, a re-test was performed that resulted in acceptable results (165 cfm ± 328 cfm).
On October 6, 2017, at 2146 hours0.0248 days <br />0.596 hours <br />0.00355 weeks <br />8.16553e-4 months <br />, this condition was reported (ENS #53003) in accordance with 10 CFR 50.72(b)(3)(v)(D) as an event or condition that, at the time of discovery, could have prevented the fulfillment of the safety function needed to mitigate the consequences of an accident. This is also reportable in accordance with the corresponding criteria of 10 CFR 50.73(a)(2)(v)(D). In addition, since the gaskets are assumed to have been out of position since installation in 2012/2013, this condition is being reported in accordance with 10 CFR 50.73(a)(2)(i)(B) as a condition prohibited by TS 3.7.3 due to not meeting SR 3.7.3.4.
comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to 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.
CAUSE OF EVENT
The direct cause was the door gaskets being out of position on the "A" CREOAS filter train. During removal, the gaskets were not flush with the door and were glued to a single spot on the top, middle and bottom section of the gasket strip. The gaskets likely rolled out of position due to not being completely glued onto the surface of the channel. The exact point in time of when the gaskets rolled out of position cannot be determined. Since there is no evidence that the personnel opened the filter train doors causing the gaskets to roll out of position after installation of the gaskets in 2012 and 2013, it is conservatively assumed that the gasket rolled out of position during the gasket replacement.
ANALYSIS/SAFETY SIGNIFICANCE
During the October 2017 tracer gas testing of the CREOAS trains, the unfiltered inleakage with the 'A' CREOAS train in operation was determined to be 680 cfm (including measurement uncertainty). Operation of CREOAS is assumed in two Final Safety Analysis Report (FSAR) Chapter 15 dose consequence analyses (Fuel Handling Accident and Design Basis Accident — Loss of Coolant Accident (DBA-LOCA)).
The Fuel Handling Accident calculation was performed using 700 cfm of unfiltered inleakage to bound the October 2017 testing results. The results of this analysis showed dose consequence to the control room operator remained less than the regulatory limit of 5 Rem TEDE.
The DBA-LOCA analysis was also performed using 700 cfm of unidentified inleakage to bound the October 2017 testing results. In the analysis, a bounding measured value from 2011 through 2017 was used for the Engineered Safety Features (ESF) recirculation leakage while other assumptions (e.g. secondary containment bypass leakage, containment leakage) were maintained at the design values in order to preserve the conservatism of the calculation. The results of this analysis showed dose consequence to the control room operator remained less than the regulatory limit of 5 Rem TEDE.
Based on engineering analysis of the event, the limiting dose consequences remained within the regulatory limit of 5 Rem TEDE and the Control Room Habitability Envelope (CRHE) remained capable of performing its safety function. This event will not be counted as a safety system functional failure (SSFF) for the NRC performance indicator based on the engineering analysis supporting the system's ability to fulfill the safety function.
CORRECTIVE ACTIONS
The key corrective action is as follows:
1. The gaskets on the filter train and the fan plenum door were repaired.
2. A re-test was performed that resulted in acceptable results.
3. A step in the work scope of the preventive maintenance activity for replacing the gaskets will be added to state, "Ensure gasket is entirely glued into the channel such that the gasket is in contact with the entire channel.
comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to 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.
2017
COMPONENT FAILURE INFORMATION
Information for gasket:
Manufacturer: Farr Company Model: N-228 - 006 - 01
PREVIOUS SIMILAR EVENTS
dated March 3, 2017 was similar in that the cause was related to a gasket issue.
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05000388/LER-2017-010 | Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switches LER 17-010-00 for Susquehanna, Unit 2 Regarding Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switches | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000387/LER-2017-001 | Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors LER 17-001-00 for Susquehanna, Unit 2, Regarding Secondary Containment Declared Inoperable Due to Airlock Doors Open Due to Sticking Door Latch | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000388/LER-2017-002 | Implementation of Enforcement Guidance Memorandum (EGM) 11-003, Revision 3 during Unit 2 Refueling LER 17-002-00 for Susquehanna, Unit 2, Regarding Implementation of Enforcement Guidance Memorandum (EGM) 11-003, Revision 3 During Unit 2 Refueling | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000387/LER-2017-002 | Secondary Containment Breach due to Simultaneous Opening of Airlock Doors LER 17-002-00 for Susquehanna, Unit 1, Regarding Secondary Containment Breach due to Simultaneous Opening of Airlock Doors | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000388/LER-2017-003 | Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000387/LER-2017-003 | Susquehanna Steam Electric Station Unit 1 05000387 LER 17-003-00 for Susquehanna, Units 1 and 2, Regarding Loss of Secondary Containment Zone 3 Due to Fan Trip | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000388/LER-2017-004 | 1 OF 3 | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000387/LER-2017-004 | Secondary Containment Declared Inoperable Due to Failure of an Exhaust Fan Breaker. LER 17-004-00 for Susquehanna, Unit 1, Regarding Secondary Containment Declared Inoperable Due to Failure of an Exhaust Fan Breaker | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000388/LER-2017-005 | Secondary Containment Declared Inoperable Due to Trip of Zone Ill Filtered Exhaust Fan | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000387/LER-2017-005 | Automatic Reactor Protection System Trip on High Neutron Flux LER 17-005-01 for Susquehanna, Unit 1 Regarding Automatic Reactor Protection System Trip on High Neutron Flux | 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000387/LER-2017-006 | Control Room Envelope In-leakage Exceeded the Technical Specification Limit LER 17-006-00 for Susquehanna, Unit 2, Regarding Secondary Containment Declared Inoperable Due to Trip of Zone II Exhaust Fan | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000388/LER-2017-007 | Secondary Containment Declared Inoperable Due to Supply Air Flow | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000387/LER-2017-007 | Secondary Containment Declared Inoperable Due to the opening of a plenum. LER 17-007-00 for Susquehanna Steam Electric Station Regarding Secondary Containment Declared Inoperable Due to Supply Air Flow | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000388/LER-2017-008 | 1 OF 3 LER 17-008-00 for Susquehanna, Unit 2, Regarding Condition Prohibited by Technical Specifications Due to a Loose Terminal Block Associated with a Primary Containment Isolation Valve | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000388/LER-2017-009 | Secondary Containment Declared Inoperable Due to Trip of Zone II Equipment Exhaust Fan | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material |
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