Event Notification Report for December 01, 2015

AGREEMENT STATE REPORT - LOST TRITIUM EXIT SIGN

The following information was provided by the State of Colorado via email:

"Event date and time: 12-1-2015, 12:15 MST. The exit sign is considered to be lost material and it is unknown what date the sign was removed or abandoned.

"Event location: 9351 Willow Court, Henderson, CO

"Event type: Lost Exit Sign Model # SLX 60, Serial Number 11-13624, 6.2 Ci, H-3, Shipped from Isolite Corporation on 4/26/2011.

"Event description: The onsite manager completed an inspection of the property. No Tritium exit sign was discovered. The exit sign is considered to be lost. The company representative will provide a written policy and procedure to resolve this from happening in the future."

Event Report ID No.: CO15-I15-35

THIS MATERIAL EVENT CONTAINS A "LESS THAN CAT 3" LEVEL OF RADIOACTIVE MATERIAL

Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf

SECONDARY CONTAINMENT INOPERABLE DUE TO REACTOR BUILDING AIRLOCK DOORS BEING OPENED SIMULTANEOUSLY

"On December 1, 2015 at 1245 EST, Secondary Containment became inoperable due to the failure to meet a Surveillance Requirement (SR 3.6.4.1.3) on Unit 2.

"The inoperability was caused when RB [Reactor Building] airlock doors were inadvertently opened simultaneously.

"Secondary Containment was restored December 1, 2015 at 1246 EST when the doors were closed.

"This event is being reported under 10 CFR 50.72(b)(3)(v)(c) and per the guidance of NUREG 1022, Rev 3, section 3.2.7 as a loss of a Safety Function. There is no redundant Susquehanna Secondary Containment system."

The licensee notified the NRC Resident Inspector.

MANUAL REACTOR TRIP AFTER STEAM GENERATOR FEED PUMP TRIP

"On 12/01/2015 at 1820 EST, the Main Control Room received a 22 Steam Generator Feed Pump trip. The 22 Steam Generator Feed Pump was not able to be reset and the Main Control Room manually tripped the Unit 2 Reactor. The licensee entered Emergency Operating Procedure (EOP)-0, 'Post Trip Immediate Actions' and all safety functions were met.

"At 1833, Unit 2 transitioned into EOP-1, 'Uncomplicated Reactor Trip.'

At 1841, Unit 2 transitioned into Operating Procedure #4 , 'Plant Shutdown from Power to Hot Stand-by.'

"The plant is stable in Mode 3."

All control rods inserted fully on the reactor trip. No primary or secondary safety relief valves lifted. The steam generators are being fed by the 21 steam generator feed pump and decay heat is being dumped to the condenser via the steam dumps. The electric plant is in a normal shutdown electrical lineup and there was no impact on Unit 1. Unit 1 continues to operate at 100 percent power. The cause of the 22 steam generator feed pump trip is still under investigation.

The licensee notified the NRC Resident Inspector.

INVALID EMERGENCY FEEDWATER ACTUATION

"On December 1, 2015, at 2119 EST, with Unit 1 in power operation mode, during a planned maintenance activity, an invalid Heat Sink Protection System (HSPS) actuation occurred. At the time of the event, electrical maintenance technicians were verifying a HSPS relay contact state using an electrical test meter. The contact was being verified open by recording both voltage and resistance readings across the contact. The technicians first measured voltage. No voltage was found, indicating the relay contact was open, as expected. The technicians then measured for resistance across the open contact. Test meters have lower circuit impedance when measuring resistance as opposed to voltage, which can result in electrically bridging across open contacts. When the meter was installed across the open contact to obtain the resistance reading, the HSPS actuation circuit logic was completed and the inadvertent HSPS actuation occurred. The HSPS actuation resulted in the steam driven Emergency Feedwater (EFW) pump automatically starting and control valves receiving actuation set point signals. There was no emergency feed water injection into the steam generators. At the time of the inadvertent HSPS actuation, steam generator operating levels were above the HSPS actuation setpoint.

''The specific train and system that actuated was the Heat Sink Protection System, Emergency Feedwater System Actuation on Loss of All Reactor Coolant Pumps (RCP) Train A.

''The HSPS Loss of all RCP Train A actuation was complete.

''The EFW valves and EFW steam driven pump started and functioned successfully.

"This is reported under 10 CFR 50.73(a)(2)(iv)(A) for an invalid actuation of HSPS Loss of all RCP Train A and in accordance with 10 CFR 50.73(a)(1), this notification of the invalid actuation is provided in lieu of a written LER.

"The Licensee notified the NRC Resident Inspector."