05000387/LER-2017-001

LER-2017-001, Secondary Containment Breach Due to Simultaneous Opening of Airlock Doors

Susquehanna Steam Electric Station Unit 1
Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material
3872017001R00 - NRC Website

LER 17-001-00 for Susquehanna, Unit 2, Regarding Secondary Containment Declared Inoperable Due to Airlock Doors Open Due to Sticking Door Latch

ML17125A030
Person / Time
Site:	Susquehanna
Issue date:	05/05/2017
From:	Berryman B Susquehanna, Talen Energy
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
PLA-7599 LER 17-001-00
Download: ML17125A030 (4)

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 e-mail to Infocollects.Resource@nrc.gov, and to the Desk Olficer, 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.

-1',4114,1 Susquehanna Steam Electric Station

CONDITIONS PRIOR TO EVENT

Unit 1 — Mode 1, approximately 100 percent Rated Thermal Power Unit 2 — Mode 1, approximately 100 percent Rated Thermal Power There were no systems, structures or components that were inoperable at the start of the event and contributed to the event.

EVENT DESCRIPTION

On January 17, 2017 at approximately 11:45, three employees with a group of visitors were exiting the Unit 1 Reactor Building [El IS Component Identifier: AL] Airlock [EllS Component Identifier: DR] on Elevation 676'. While processing through the card reader, an individual in the group opened the Turbine Building [El IS Component Identifier: NM] airlock door prior to the Reactor Building airlock door being completely closed. Upon hearing the alarm, security, who was present to help process visitors through the card reader, notified Security Control and the Shift Manager. 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 Human Performance Tools including Self-Check (STAR).

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).

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 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.

Susquehanna Steam Electric Station

PREVIOUS SIMILAR EVENTS

The following recent LERs involved loss of Secondary Containment due to door issues:

Airlock Doors," dated January 26, 2017.

Open Due to a Human Performance Error," dated November 21, 2016.

Airlock Doors," dated December 1, 2016.

Open Due to a Human Performance Error," dated, August 17, 2016.

Open Due to Human Performance Error During Security Response," dated December 21, 2016.

Open Due to a Human Performance Error," dated June 15, 2016.

Open Due to a Human Performance Error," dated June 9, 2016.

Opening of Double Airlock Doors," dated June 9, 2016.

Open Due to a Human Performance Error," dated May 16, 2016.

Doors on Elevation 779 of the Unit 2 Reactor Building being Opened at the Same Time," dated May 10, 2016.

Open Due to Random Occurrence," dated April 18, 2016.

Open Due to Random Occurrence," dated April 18, 2016.