05000387/LER-2016-001, Regarding Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors Due to Degraded Latch Mechanism

Regarding Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors Due to Degraded Latch Mechanism

ML16145A123
Person / Time
Site:	Susquehanna
Issue date:	05/24/2016
From:	Franke J Susquehanna, Talen Energy
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
PLA-7470 LER 16-001-00
Download: ML16145A123 (5)

LER-2016-001, Regarding Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors Due to Degraded Latch Mechanism

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 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)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i)
3872016001R00 - NRC Website

text

MAY 2 4 2016 Jon A. Franke Susquehanna Nuclear, LLC Site Vice President 769 Salem Boulevard Berwick, PA 18603 Tel. 570.542.2904 Fax 570.542.1504 Jon.Franke@TalenEnergy.com U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 SUSQUEHANNA STEAM ELECTRIC STATION LICENSEE EVENT REPORT 50-388(387)/2016-001-00 UNIT 2 LICENSE NO. NPF-22 UNIT 1 LICENSE NO. NPF-14 PLA-7470 TALEN~

ENERGY 10 CFR 50.73 Docket No. 50-388 50-387 Attached is Licensee Event Report (LER) 50-388(387)/2016-001-00. This LER repmis a condition that could have prevented fulfillment of the Secondary Containment integrity safety function. In this event, both doors for one of the secondary containment access airlock were briefly opened simultaneously due to a degraded door latch mechanism.

This LER is being submitted pursuant to the requirements of 10 CFR 50.73(a)(2)(v)(C).

There were no actual consequences to the health and safety of the public as a result of this event.

This letter contains no new regulatory commitments.

~~

~ J~h-.r;~/-<

J. A. Franke Attachment: LER 50-388(387)/2016-001-00 Copy:

NRC Region I Mr. J. E. Greives, NRC Sr. Resident Inspector Ms. T. E. Hood, NRC Project Manager Mr. M. Shields, PA DEP/BRP

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2018 (11-2015)

, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

r* PAGE Susquehanna Steam Electric Station Unit 2 05000388 1 of4

4. TITLE Secondary Containment Breach due to Simultaneous Opening of Airlock Doors Due to Degraded Latch Mechanism

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED YEAR I SEQUENTIAL I REV FACILITY NAME DOCKET NUMBER MONTH DAY YEAR NO.

MONTH DAY YEAR Susquehanna Steam Electric Station Unit 1 05000387 NUMBER FACILITY NAME DOCKET NUMBER 03 29 2016 2016

- 001

- 00 05

~4--

2016 05000

9. OPERATING MODE

11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §:(Check all that apply)

D 20.2201(b)

D 20.2203(a)(3)(i)

D 50.73(a)(2)(ii)(A)

D 50.73(a)(2)(viii)(A) 1 0 20.2201(d)

D 20.2203(a)(3)(ii) 0 50.73(a)(2)(ii)(B)

D 50.73(a)(2)(viii)(B) 0 20.2203(a)(1)

D 20.2203(a)(4) 0 50.73(a)(2)(iii) 0 50.73(a)(2)(ix)(A) 0 20.2203(a)(2)(i)

D 50.36(c)(1 )(i)(A) 0 50.73(a)(2)(iv)(A) 0 50.73(a)(2)(x)

D 20.2203(a)(2)(ii) 0 50.36(c)(1 )(ii)(A) 0 50.73(a)(2)(v)(A) 0 73.71(a)(4)

10. POWER LEVEL D 20.2203(a)(2)(iii) 0 50.36(c)(2) 0 50.73(a)(2)(v)(B) 0 73.71(a)(5)

D 20.2203(a)(2)(iv) 0 50.46(a)(3)(ii)

~ 50.73(a)(2)(v)(C) 0 73.77(a)(1) 100 D 20.2203(a)(2)(v) 0 50.73(a)(2)(i)(A)

D 50.73(a)(2)(v)(D)

D 73.77(a)(2)(i) 0 20.2203(a)(2)(vi)

D 50.73(a)(2)(i)(B)

D 50.73(a)(2)(vii)

D 73.77(a)(2)(ii)

D 50.73(a)(2)(i)(C) 0 OTHER Specify in Abstract below or in

ANALYSIS/SAFETY SIGNIFICANCE

, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

2. DOCKET NUMBER

3. LER NUMBER 05000388 YEAR I

SEQUENTIAL I

REV NUMBER NO.

2016

- 001

- 00 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

As discussed above, the cause of this event was attributed to normal wear of the airlock door latch. A work order was written to investigate and repair the Door-120A latch as necessary. Maintenance lubricated and tightened screws on the latch mechanism; the door was then successfully tested and confirmed operable by Operations.

No regulatory commitments are associated with this report.

COMPONENT FAILURE INFORMATION

Reactor Building Elevation 676' Door-120A-Normal Wear.

NRC FORM 366 (11-2015)

PREVIOUS SIMILAR EVENTS

, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

2. DOCKET NUMBER

3. LER NUMBER YEAR I

SEQUENTIAL I

REV NUMBER NO.

05000388 2016

- 001

- 00 The following recent LERs involving loss of Secondary Containment due to door issues:

LER 50-387(388)/ 2016-001-00 (PLA7453), "Secondary Containment Declared Inoperable Due to an Airlock Door Open Due to Random Occurrence," dated April 18, 2016.

LER 50-387(388)/2016-002-00 (PLA7 454 ), "Secondary Containment Declared Inoperable due to an Airlock Doors Open Due to Random Occurrence," dated April 18, 2016.

LER 50-387/ 2015-011-00 (PLA7 432), "Secondary Containment Declared Inoperable Due to an Airlock Door that had not been Properly Latched," dated January 29, 2016.

LER 50-387(388) 2015-006-00 (PLA7383), "Secondary Containment Declared Inoperable Due to Secondary Containment Boundary Door 1 04-R Breached," dated September 18, 2015.

LER 50-387/ 2015-004-00 (PLA7353), "Secondary Containment Inoperable due Secondary Containment Boundary Door Found Ajar," dated June 25, 2015.

LER 50-387(388)/ 2015-002-00 (PLA7329), "Secondary Containment lnoperability due Failure to Meet Technical Specification Surveillance Requirement 3.6.4.1.1," dated June 10, 2015.

LER 50-387(388)/2014-002-00 (PLA7155), "Secondary Containment Door found Ajar," dated April 9, 2014.

LER 50-388(387)/ 2014-001-00 (PLA7270), "Both Doors of a Secondary Containment Personnel Airlock Momentarily Open Due to a Personnel Error Resulting in Entry into Secondary Containment Technical Specification Limiting Condition for Operation," dated December 31, 2014.

NRC FORM 366 (11-2015)

MAY 2 4 2016 Jon A. Franke Susquehanna Nuclear, LLC Site Vice President 769 Salem Boulevard Berwick, PA 18603 Tel. 570.542.2904 Fax 570.542.1504 Jon.Franke@TalenEnergy.com U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 SUSQUEHANNA STEAM ELECTRIC STATION LICENSEE EVENT REPORT 50-388(387)/2016-001-00 UNIT 2 LICENSE NO. NPF-22 UNIT 1 LICENSE NO. NPF-14 PLA-7470 TALEN~

ENERGY 10 CFR 50.73 Docket No. 50-388 50-387 Attached is Licensee Event Report (LER) 50-388(387)/2016-001-00. This LER repmis a condition that could have prevented fulfillment of the Secondary Containment integrity safety function. In this event, both doors for one of the secondary containment access airlock were briefly opened simultaneously due to a degraded door latch mechanism.

This LER is being submitted pursuant to the requirements of 10 CFR 50.73(a)(2)(v)(C).

There were no actual consequences to the health and safety of the public as a result of this event.

This letter contains no new regulatory commitments.

~~

~ J~h-.r;~/-<

J. A. Franke Attachment: LER 50-388(387)/2016-001-00 Copy:

NRC Region I Mr. J. E. Greives, NRC Sr. Resident Inspector Ms. T. E. Hood, NRC Project Manager Mr. M. Shields, PA DEP/BRP

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2018 (11-2015)

, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

r* PAGE Susquehanna Steam Electric Station Unit 2 05000388 1 of4

4. TITLE Secondary Containment Breach due to Simultaneous Opening of Airlock Doors Due to Degraded Latch Mechanism

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED YEAR I SEQUENTIAL I REV FACILITY NAME DOCKET NUMBER MONTH DAY YEAR NO.

MONTH DAY YEAR Susquehanna Steam Electric Station Unit 1 05000387 NUMBER FACILITY NAME DOCKET NUMBER 03 29 2016 2016

- 001

- 00 05

~4--

2016 05000

9. OPERATING MODE

11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §:(Check all that apply)

D 20.2201(b)

D 20.2203(a)(3)(i)

D 50.73(a)(2)(ii)(A)

D 50.73(a)(2)(viii)(A) 1 0 20.2201(d)

D 20.2203(a)(3)(ii) 0 50.73(a)(2)(ii)(B)

D 50.73(a)(2)(viii)(B) 0 20.2203(a)(1)

D 20.2203(a)(4) 0 50.73(a)(2)(iii) 0 50.73(a)(2)(ix)(A) 0 20.2203(a)(2)(i)

D 50.36(c)(1 )(i)(A) 0 50.73(a)(2)(iv)(A) 0 50.73(a)(2)(x)

D 20.2203(a)(2)(ii) 0 50.36(c)(1 )(ii)(A) 0 50.73(a)(2)(v)(A) 0 73.71(a)(4)

10. POWER LEVEL D 20.2203(a)(2)(iii) 0 50.36(c)(2) 0 50.73(a)(2)(v)(B) 0 73.71(a)(5)

D 20.2203(a)(2)(iv) 0 50.46(a)(3)(ii)

~ 50.73(a)(2)(v)(C) 0 73.77(a)(1) 100 D 20.2203(a)(2)(v) 0 50.73(a)(2)(i)(A)

D 50.73(a)(2)(v)(D)

D 73.77(a)(2)(i) 0 20.2203(a)(2)(vi)

D 50.73(a)(2)(i)(B)

D 50.73(a)(2)(vii)

D 73.77(a)(2)(ii)

D 50.73(a)(2)(i)(C) 0 OTHER Specify in Abstract below or in

CONDITIONS PRIOR TO EVENT

Unit 2-Mode 1, 100 percent Rated Thermal Power Unit 1 - Mode 5, 0 percent Rated Thermal Power

EVENT DESCRIPTION

, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

2. DOCKET NUMBER 05000388 YEAR I

2016

3. LER NUMBER SEQUENTIAL I

NUMBER

- 001 REV NO.

- 00 On March 29, 2016 at approximately 23:00, two employees leaving the Unit 2 Turbine Building [EllS System Identifier: NM] entered the Turbine Building to Reactor Building airlock [EllS Component Identifier: AL] on elevation 676'. Prior to opening the airlock door [EllS Component Identified: DR], employees verified a green light was present, indicating the opposite airlock door was closed. The first employee entered the airlock while the other employee held the Turbine building door. As the second employee entered into the airlock, the airlock alarm was heard. At this time, a rush of air was observed from the Reactor Building [EllS System Identifier: NG] side of the airlock, forcing the door open (Door 120A). Both individuals quickly closed the doors, followed by a peer check to verify each door was properly shut. The individuals then proceeded through the Reactor Building door to the nearest phone and informed the Control Room [EllS System Identifier: NA] of the event.

CAUSE OF EVENT

The direct cause of this event is normal wear of the airlock door latch. Based on investigation performed, the Door 120A latch was determined to be sticking inside the crash bar. This prevented the Reactor Building airlock door from properly latching and staying latched when differential pressure was applied to the door upon entering the airlock from the Unit 2 Turbine Building side.

NRC FORM 366 (11-2015)

Paqe 3 of 4

ANALYSIS/SAFETY SIGNIFICANCE

, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

2. DOCKET NUMBER

3. LER NUMBER 05000388 YEAR I

SEQUENTIAL I

REV NUMBER NO.

2016

- 001

- 00 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

As discussed above, the cause of this event was attributed to normal wear of the airlock door latch. A work order was written to investigate and repair the Door-120A latch as necessary. Maintenance lubricated and tightened screws on the latch mechanism; the door was then successfully tested and confirmed operable by Operations.

No regulatory commitments are associated with this report.

COMPONENT FAILURE INFORMATION

Reactor Building Elevation 676' Door-120A-Normal Wear.

NRC FORM 366 (11-2015)

PREVIOUS SIMILAR EVENTS

, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

2. DOCKET NUMBER

3. LER NUMBER YEAR I

SEQUENTIAL I

REV NUMBER NO.

05000388 2016

- 001

- 00 The following recent LERs involving loss of Secondary Containment due to door issues:

LER 50-387(388)/ 2016-001-00 (PLA7453), "Secondary Containment Declared Inoperable Due to an Airlock Door Open Due to Random Occurrence," dated April 18, 2016.

LER 50-387(388)/2016-002-00 (PLA7 454 ), "Secondary Containment Declared Inoperable due to an Airlock Doors Open Due to Random Occurrence," dated April 18, 2016.

LER 50-387/ 2015-011-00 (PLA7 432), "Secondary Containment Declared Inoperable Due to an Airlock Door that had not been Properly Latched," dated January 29, 2016.

LER 50-387(388) 2015-006-00 (PLA7383), "Secondary Containment Declared Inoperable Due to Secondary Containment Boundary Door 1 04-R Breached," dated September 18, 2015.

LER 50-387/ 2015-004-00 (PLA7353), "Secondary Containment Inoperable due Secondary Containment Boundary Door Found Ajar," dated June 25, 2015.

LER 50-387(388)/ 2015-002-00 (PLA7329), "Secondary Containment lnoperability due Failure to Meet Technical Specification Surveillance Requirement 3.6.4.1.1," dated June 10, 2015.

LER 50-387(388)/2014-002-00 (PLA7155), "Secondary Containment Door found Ajar," dated April 9, 2014.

LER 50-388(387)/ 2014-001-00 (PLA7270), "Both Doors of a Secondary Containment Personnel Airlock Momentarily Open Due to a Personnel Error Resulting in Entry into Secondary Containment Technical Specification Limiting Condition for Operation," dated December 31, 2014.

NRC FORM 366 (11-2015)