Event Notification Report for August 01, 2016

PLANT SHUTDOWN DUE TO PRESSURE BOUNDARY LEAKAGE GREATER THAN ALLOWABLE LIMIT

"On August 1, 2016 at 0342 EDT St. Lucie Unit 1 commenced a unit shutdown required by Technical Specifications due to Reactor Coolant System Pressure Boundary Leakage in excess of the allowable limit of zero leakage. The leak was initially identified on July 31, 2016 at 2115 EDT as not Pressure Boundary leakage. After further analysis, the leak was determined to be Reactor Coolant System Pressure Boundary leakage at 0123 on August 1, 2016. The leakage is estimated as less than one tenth of a gallon per minute and is not impacting the ability to shut down the unit. Additional impact of the leak is under evaluation.

"This report is submitted in accordance with 10CFR50.72(b)(2)(i) as 'The initiation of any nuclear plant shutdown required by the plant's Technical Specifications.'

"The location of the leak is on the Instrumentation piping welded connection at Flow Element FE-3311 attached to [the] Emergency Core Cooling System Injection header to Reactor Coolant System Loop 1A2. The leak activity is 0.167 microCuries per ml."

The NRC Resident Inspector has been notified.

* * * RETRACTION AT 1335 EDT ON 09/23/16 FROM RICHARD SCISCENTE TO JEFF HERRERA * * *

"The purpose of this notification is to retract a previous report made on EN 52138. NRC notification was initially made as a result of a plant shutdown required by technical specifications (TS) for Reactor Coolant System (RCS) pressure boundary leakage.

"Subsequent to the initial report, St. Lucie has determined that the RCS leakage was from a seal weld on a threaded connection that was not pressure boundary leakage. However, the leak was non-isolable and required RCS depressurization to allow immediate investigation to ensure there were no faults in a RCS component body or pipe wall.

"The leakage was estimated to be less than one tenth of a gallon per minute and did not impact the ability to shut down the unit. No TS limits were exceeded during this event.

"Therefore, the plant shutdown to investigate and correct leakage past the seal weld of a threaded connection does not meet the reporting requirements of 10 CFR 50.72 or 10 CFR 50.73."

The NRC Resident Inspector has been notified.

Notified the R2DO (Blamey).

AGREEMENT STATE REPORT - STOLEN MOISTURE DENSITY GAUGE

The licensee reported a stolen Troxler Model 3430 Moisture/Density gauge, Serial Number 27320 between midnight and 0600 CDT. The Troxler gauge was locked and stored at the licensee's facility. The Topeka Police Department was notified.

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

UNINTENTIONAL RELEASE OF HALON

"At 1118 [CDT] during planned maintenance activities there was an unintentional release of approximately 146.5 pounds of Halon gas into an enclosed room in the Unit-2 Electrical Auxiliary Building. There was no impact to plant operations or plant personnel. The room was verified by station Safety Personnel to be safe for normal access.

"At 1518, Region 12 (Houston) of the Texas Commission of Environmental Quality (TCEQ) was notified of an event which met the requirements of 'Emission Event' for the TCEQ of a HALON release that exceeded the reportable quantity threshold of 100 pounds in a 24 hour period. No further actions are required by the TCEQ at this time and no press release is planned. The halon discharge was contained within the site protected area. Therefore, this event is not significant with respect to the health and safety of the public."

The licensee has notified the NRC Resident Inspector.

AGREEMENT STATE REPORT - SHUTTER MALFUNCTION DUE TO HIGH VIBRATION

The following information was received via facsimile:

"On August 1, 2016, the Department [Pennsylvania Department of Environmental Protection, Bureau of Radiation Protection] was notified by Georgia Pacific that a shutter handle had fallen off. This made the shutter inoperable in the closed position. It is initially reportable per 10 CFR 30.50(b)(2).

"During a routine maintenance check, the licensee became aware of a gauge with an inoperable shutter. The gauge is located in a remote area with high vibration and the handle to the shutter seemed to have dislodged due to this, making it unusable. The gauge was put out of service until repairs can be completed by a licensed contractor. No exposures have occurred.

"The shutter is in the closed position and the gauge is out of service and secure. There was no other damage to the gauge. A reactive inspection is planned by the Department.

"Radionuclide: Cs-137
Manufacturer: Ronan
Model: SA-1
Serial Number: M7419
Activity: 40 mCi"

Pennsylvania Event Report ID No.: PA160021