Event Notification Report for October 16, 2012

AGREEMENT STATE REPORT - RADIOGRAPHY CAMERA SOURCE DISCONNECT

The following report was received from the State of Texas Radiation Branch via facsimile:

"On October 17, 2012, the Agency [Texas Radiation Branch] was notified by the licensee that on October 16, 2012, a radiography source had disconnected from the drive cable during radiography at a field location. The radiographers were using a SPEC 150 exposure device [redacted]. The radiographers had completed an exposure and as they were surveying the exposure device, the radiographer noted that the dose rates at the front of the device were higher than expected. The radiographers contacted their Radiation Safety Officer. A source recovery team was sent to the location and the source was recovered without incident. The licensee read the Instadose dosimeters for the individuals involved in the event and no over exposures occurred. No additional exposure to a member of the general public occurred due to this event. The licensee was not able to determine the cause for the disconnect. The exposure device and the crank-out device the radiographers were using are being sent to the manufacturer for inspection."

Texas Incident #: I-8994

SHUTDOWN COOLING ISOLATION CAPABILITY LOST

"On October 16, 2012, at 0529 EDT, with the reactor in mode 4 and one operable channel for the Residual Heat Removal (RHR) shutdown cooling isolation function, as permitted by TS 3.3.6.1, Operators identified a rising reactor water level indication on instruments associated with the 3A reactor water level reference leg while actual level remained constant. At 0700 EDT, Operators determined this condition rendered the RHR shutdown cooling isolation function inoperable; specifically, an isolation signal for RHR shutdown cooling based on a low reactor water level. In accordance with Tech Spec 3.3.6.1 Required Action J.1, immediate action was initiated to restore isolation capability. RHR shutdown cooling isolation capability was restored at 1040 EDT by changing in-service RHR shutdown cooling systems.

"This event could have prevented the fulfillment of a safety function, 10 CFR 50.72(b)(3)(v), at time of discovery to mitigate the consequences of an accident (D)."

The licensee has notified the NRC Resident Inspector.

PROCESS GAUGE SHUTTER STUCK OPEN

The RSO reported a shutter problem on a fixed mounted process gauge manufactured by Vega Americas (Model SHF-2B) containing an 800 mCi Cs -137 source. The shutter problem was discovered during a semi-annual shutter check when it was determined that the shutter would not close. The shutter is normally always open to support the manufacturing process and the failure to close does not pose any personnel exposure risk. The RSO is following up with a vendor to repair the shutter onsite.

UNUSUAL EVENT DECLARED DUE TO EARTHQUAKE FELT ON-SITE

"An Unusual Event was declared at 1920 EDT, HU1 - Earthquake felt in the plant (Control Room), and confirmed by calling the Manchester Dispatch Office.

"Post event walkdowns indicate no reports of damage at the station. Walkdowns of station structures and systems continue.

"Plant is stable in Mode 5 planned refueling outage.

"No adverse impacts to shutdown cooling.

"The station seismic monitor is currently out of service for a scheduled calibration."

The licensee is exiting a refueling outage. The earthquake was felt by the site at 1914 EDT. The United States Geological Survey website indicates that an earthquake of magnitude 4.0 centered 3 miles west of Hollis Center, Maine occurred at this time.

The licensee is currently in a Train 'B' system outage. All Train 'A' systems are functioning as required.

The licensee has notified the NRC Resident Inspector and State authorities. No media or press release is anticipated at this time. The Headquarters Operations Officer has notified other FEDS (FEMA, DHS, DHS NICC and Nuclear SSA via email).

* * * UPDATE FROM SEAN RILEY TO PETE SNYDER AT 0212 ON 10/17/12 * * *

"The Unusual Event was terminated at 0149 EDT. Initiating condition was HU-1 due to the earthquake felt at the plant and confirmed by calling Manchester Dispatch Office. Information obtained by seismic monitoring system confirmed no additional escalation warranted. Site walkdown of key systems revealed no damage from the earthquake. All systems required for the current mode of operation were not adversely affected and remain in operation. "

The licensee will notify the NRC Resident Inspector. Notified R1DO (Welling), NRR (Bahadur), IRD (Grant) and other FEDS (FEMA, DHS, DHS NICC and Nuclear SSA via email).

ALL FOUR EMERGENCY DIESEL GENERATORS AUTO-START ON VALID UNDERVOLTAGE SIGNAL

"On October 16, 2012, Watts Bar Nuclear Plant Unit 1 experienced a momentary loss of power to the 1B 6.9 KV Shutdown board. This resulted in an emergency start of all 4 Emergency Diesel Generators due to actuation of the designed undervoltage EDG start signal. A manual transfer of the shutdown board from the Normal power supply to the Alternate was in progress to support maintenance. The momentary loss of power lasted approximately 2 seconds, which caused load shed and Diesel Generator start to occur.

"Core cooling was maintained throughout the transient.

"This condition is being reported under 10 CFR 50.72 (b)(3) (iv) (A).

"All safety systems responded as designed. The unit remains stable in Mode 5.

"The cause for this failure is not yet known. Investigation is in progress.

"The NRC Senior Resident has been notified."

PLANNED TECHNICAL SUPPORT CENTER (TSC) MAINTENANCE

"At approximately 0800 on October 16, 2012 pre-planned maintenance will be performed that will affect the Technical Support Center (TSC) ventilation system. The scope of the maintenance is to inspect and clean all air handler units, fans, and outside air condensing units that support TSC ventilation. This maintenance is expected to be performed and completed within approximately 13 hours. If an emergency condition should occur, the ventilation system will be restored, but potentially not within the time required for activation of the TSC. In addition, the Harris Nuclear Plant (HNP) emergency plan has procedural guidance for use of an alternate location in the event the TSC is not habitable.

"This event is reportable per 10 CFR 50.72(b)(3)(xiii) as described in NUREG-1022, Rev. 2 since this work activity affects an emergency response facility for the duration of the maintenance."

The NRC Resident Inspector has been notified.