05000387/LER-2016-013

LER-2016-003, Secondary Containment Declared Inoperable Due to Simultaneous Opening of Double 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
3872016003R00 - NRC Website

LER 16-013-00 for Susquehanna, Unit 1, Regarding Secondary Containment Declared Inoperable Due to Simultaneous Opening of Double Airlock Doors

ML16161A474
Person / Time
Site:	Susquehanna
Issue date:	06/09/2016
From:	Franke J A Susquehanna, Talen Energy
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
PLA-7492 LER 16-013-00
Download: ML16161A474 (4)

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 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.

3. LER NUMBER

- 013 2016

CONDITIONS PRIOR TO EVENT

Unit 1 — Mode 5, 0 percent Rated Thermal Power Unit 2 — Mode 1, 100 percent Rated Thermal Power There were no structures, systems, or components that were inoperable at the start of the event that contributed to the event. Zone 1 of Secondary Containment (applicable to Unit 1 only) was established at 17:00 on 04/12/16 and was required by TS 3.6.4.1 at the time of this event.

EVENT DESCRIPTION

On April 12, 2016 at approximately 2020 hours0.0234 days <br />0.561 hours <br />0.00334 weeks <br />7.6861e-4 months <br />, a Susquehanna employee was in the process of exiting the Unit 1 Reactor Building via a double door airlock leading to the Unit 1 Turbine Building. The individual inserted their badge into a security related badge reader to access the airlock and received a green light.

While opening the Reactor Building side door, employees from the Turbine Building side entered the airlock.

The airlock air horn alarm activated as designed since both doors were simultaneously opened. The individual did not observe the airlock indication light prior to entry, which is designed to indicate red while the airlock is being utilized.

With both airlock doors open simultaneously during a period in which Secondary Containment was required, Surveillance Requirement (SR) 3.6.4.1.3 was not met.

This Licensee Event Report (LER) is being submitted in accordance with 10 CFR 50.73(a)(2)(v)(C) as a condition which, at the time of discovery, could have prevented the fulfillment of a safety function.

CAUSE OF EVENT

An interview was conducted with the individuals involved immediately following the event. Information obtained during the interviews was used in performing the condition report evaluation. The condition report evaluation determined the direct cause of the event was less than adequate situational awareness, since the individual stated they did not confirm that other personnel were not entering the airlock.

ANALYSIS/SAFETY SIGNIFICANCE

An engineering evaluation was performed and concluded that secondary containment could have performed its safety function of isolating, as assumed in the accident analysis, and also of re-establishing 0.25 inches vacuum (drawdown) within the assumed accident analysis time (10 minutes). Therefore, the subject event did not cause a loss of safety function. As a result this event will not be counted as a safety system functional failure (SSFF) for the NRC performance indicator.

- 00 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 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.

CORRECTIVE ACTIONS

In addition to coaching the individual who committed the error, reinforcement of the expectations related to use of Secondary Containment Boundary doors was provided in the next daily departmental meetings to improve human performance associated with airlock door use.

PREVIOUS SIMILAR EVENTS

The following are recent LERs involving loss of secondary containment due to door issues:

May 31, 2016.

16, 2016.

to Random Occurrence," dated April 18, 2016.

to Random Occurrence," dated April 18, 2016.

Not Been Properly Latched," dated January 29, 2016.

Boundary Door 104-R Breached," dated September 18, 2015.

Found Ajar," dated June 25, 2015.

Surveillance Requirement 3.6.4.1.1," dated May 11, 2015 Personnel Error Resulting in Entry into Secondary Containment Technical Specification Limiting Condition for Operation," dated December 31, 2014