On March 2, 2017 at approximately 10:30, three employees were entering the Unit 2 Airlock on elevation 676' from the Reactor Building door. After entering the airlock, one employee opened the second airlock door prior to the first door being closed, resulting in an alarm. This resulted in not meeting Technical Specification 3.6.4.1 Surveillance Requirement 3.6.4.1.3, which requires that one secondary containment access door in each access opening is closed.
The cause of this event was determined to be less than adequate Situational Awareness.
This condition requires reporting in accordance with 10 CFR 50.73(a)(2)(v)(C) as having both Secondary Containment airlock doors momentarily open simultaneously results in a condition that could have prevented fulfillment of a safety function.
There were no actual consequences to the health and safety of the public as a result of this event. |
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 Infocollects.Resource@nrc.00v. and to the Desk Officer, Office of Information and Regulatory Affairs, 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.
klc I- 1 FACILITY NAME 2. DOCKET NUMBER 3. LER NUMBER Susquehanna Steam Electric Station Unit 2 05000-388 NUMBER NO.
CONDITIONS PRIOR TO EVENT
Unit 1 — Mode 1, approximately 100 percent Rated Thermal Power Unit 2 — Mode 1, approximately 88 percent Rated Thermal Power
EVENT DESCRIPTION
On March 2, 2017 at approximately 10:30, three employees were entering the Unit 2 Airlock [EIIS Component Identifier: AL] on elevation 676' from the Reactor Building [EIIS System Identifier: NG] door. The first employee observed the green light, swiped their badge and entered into the airlock. The two additional employees also swiped their badges and traversed into the airlock. As the first employee opened the second door within the airlock, the airlock door alarm sounded briefly as the first door was not completely closed and latched. Upon hearing the alarm, the employees promptly reported the incident to oversight and Operations.
All personnel then provided statements with respect to the event.
CAUSE OF EVENT
The cause of the event was determined to be less than adequate use of Situational Awareness.
ANALYSIS/SAFETY SIGNIFICANCE
Technical Specification 3.6.4.1 Surveillance Requirement 3.6.4.1.3 requires that one secondary containment access door in each access opening is closed. This event is being reported pursuant to 10 CFR 50.73(a)(2)(v)(C) as having both Secondary Containment airlock doors momentarily open simultaneously results in a condition that could have prevented fulfillment of a safety function to mitigate the consequences of an accident by controlling the release of radioactive material.
There was no actual safety consequence as a result of this event. Engineering analysis of this event has determined that secondary containment could have performed its safety function of isolating, as assumed in the accident analysis, and also of re-establishing 0.25 in w.g. vacuum (drawdown) within the assumed accident analysis time (10 minutes). Therefore, the subject event did not cause a loss of 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
Key corrective actions include the following:
1. Coaching was provided to the individuals involved with respect to the use of airlock doors (Complete).
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 Int ocollects.Resource@nrctiov. and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Bridget, 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.
Susquehanna Steam Electric Station Unit 2 05000-388 NUMBER NO.
PREVIOUS SIMILAR EVENTS
The following recent LERs involving loss of Secondary Containment due to door issues:
Doors," dated March 8, 2017.
Open Due to Random Occurrence," dated April 18, 2016.
Open Due to Random Occurrence," dated April 18, 2016.
had not been Properly Latched," dated January 29, 2016.
Containment Boundary Door 104-R Breached," dated September 18, 2015.
Door Found Ajar," dated June 25, 2015.
Specification Surveillance Requirement 3.6.4.1.1," dated June 10, 2015.
Momentarily Open Due to a Personnel Error Resulting in Entry into Secondary Containment Technical Specification Limiting Condition for Operation," dated December 31, 2014.
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| 05000387/LER-2017-001, Regarding Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors | Regarding Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors | 10 CFR 50.73(a)(2)(iv)(A), System Actuation
10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition
10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor
10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat
10 CFR 50.73(a)(2)(v), Loss of Safety Function
10 CFR 50.73(a)(2)(vii), Common Cause Inoperability
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
10 CFR 50.73(a)(2)(i)
10 CFR 50.73(a)(2)(x)
10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded
10 CFR 50.73(a)(2)(iii)
10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown
10 CFR 50.73(a)(2)(ix)(A), Prevented Safety Function in Multiple System
10 CFR 50.73(a)(2)(viii)(A)
10 CFR 50.73(a)(2)(viii)(B) | | 05000387/LER-2017-002, Regarding Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors | Regarding Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors | 10 CFR 50.73(a)(2)(iv)(A), System Actuation
10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition
10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor
10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat
10 CFR 50.73(a)(2)(v), Loss of Safety Function
10 CFR 50.73(a)(2)(vii), Common Cause Inoperability
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
10 CFR 50.73(a)(2)(i)
10 CFR 50.73(a)(2)(x)
10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded
10 CFR 50.73(a)(2)(iii)
10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown
10 CFR 50.73(a)(2)(ix)(A), Prevented Safety Function in Multiple System
10 CFR 50.73(a)(2)(viii)(A)
10 CFR 50.73(a)(2)(viii)(B) | | 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, Regarding Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors | Regarding Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors | 10 CFR 50.73(a)(2)(iv)(A), System Actuation
10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition
10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor
10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat
10 CFR 50.73(a)(2)(v), Loss of Safety Function
10 CFR 50.73(a)(2)(vii), Common Cause Inoperability
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
10 CFR 50.73(a)(2)(i)
10 CFR 50.73(a)(2)(x)
10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded
10 CFR 50.73(a)(2)(iii)
10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown
10 CFR 50.73(a)(2)(ix)(A), Prevented Safety Function in Multiple System
10 CFR 50.73(a)(2)(viii)(A)
10 CFR 50.73(a)(2)(viii)(B) | | 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, Regarding Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors | Regarding Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors | 10 CFR 50.73(a)(2)(iv)(A), System Actuation
10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition
10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor
10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat
10 CFR 50.73(a)(2)(v), Loss of Safety Function
10 CFR 50.73(a)(2)(vii), Common Cause Inoperability
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
10 CFR 50.73(a)(2)(i)
10 CFR 50.73(a)(2)(x)
10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded
10 CFR 50.73(a)(2)(iii)
10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown
10 CFR 50.73(a)(2)(ix)(A), Prevented Safety Function in Multiple System
10 CFR 50.73(a)(2)(viii)(A)
10 CFR 50.73(a)(2)(viii)(B) | | 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 | | 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-2017-008, Core Spray Inoperable Due to Not Meeting Seismic Requirements as a Result of a Human Performance Error | Core Spray Inoperable Due to Not Meeting Seismic Requirements as a Result of a Human Performance Error | 10 CFR 50.73(a)(2)(iv)(A), System Actuation
10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition
10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor
10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat
10 CFR 50.73(a)(2)(v), Loss of Safety Function
10 CFR 50.73(a)(2)(vii), Common Cause Inoperability
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
10 CFR 50.73(a)(2)(i)
10 CFR 50.73(a)(2)(x)
10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded
10 CFR 50.73(a)(2)(iii)
10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown
10 CFR 50.73(a)(2)(ix)(A), Prevented Safety Function in Multiple System
10 CFR 50.73(a)(2)(viii)(A)
10 CFR 50.73(a)(2)(viii)(B) | | 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 | | 05000387/LER-2017-009-01, Regarding Secondary Containment Declared Inoperable Due to Trip of Zone II Equipment Exhaust Fan | Regarding Secondary Containment Declared Inoperable Due to Trip of Zone II Equipment Exhaust Fan | 10 CFR 50.73(a)(2)(iv)(A), System Actuation
10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition
10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor
10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat
10 CFR 50.73(a)(2)(v), Loss of Safety Function
10 CFR 50.73(a)(2)(vii), Common Cause Inoperability
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
10 CFR 50.73(a)(2)(i)
10 CFR 50.73(a)(2)(x)
10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded
10 CFR 50.73(a)(2)(iii)
10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown
10 CFR 50.73(a)(2)(ix)(A), Prevented Safety Function in Multiple System
10 CFR 50.73(a)(2)(viii)(A)
10 CFR 50.73(a)(2)(viii)(B) | | 05000387/LER-2017-010-02, Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switches | Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switches | 10 CFR 50.73(a)(2)(v), Loss of Safety Function
10 CFR 50.73(a)(2)(vii), Common Cause Inoperability
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
10 CFR 50.73(a)(2)(ix)(A), Prevented Safety Function in Multiple System | | 05000388/LER-2017-010-01, Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switches | Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switches | 10 CFR 50.73(a)(2)(v), Loss of Safety Function
10 CFR 50.73(a)(2)(vii), Common Cause Inoperability
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
10 CFR 50.73(a)(2)(ix)(A), Prevented Safety Function in Multiple System |
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