Event Notification Report for September 18, 2010

POTENTIAL EXTERNAL LEAKAGE IN SOLENOID VALVE

The following notification was received via fax:

"On 9/18/10 a single solenoid valve was returned to ASCO with a reported problem of external leakage at the bonnet area below the coil housing. The valve was returned from Cooper Nuclear Station through AREVA, who was the distributor.

"The returned valve was retested at ASCO. No external leakage was observed when the valve was tested in the de-energized state. However, when the valve was tested in the energized state, the reported leakage was confirmed. The root cause of the leakage was determined to be a misaligned O-ring between the solenoid base sub-assembly and the valve body.

"The customers that were shipped affected valves are being notified of the potential non-conformance. ASCO will recommend the affected valves be returned to be retested in accordance with updated test procedures."

* * * UPDATE FROM ROBERT ARNONE TO JOE O'HARA VIA FAX AT 1308 ON 11/11/10 * * *

"In our continuing investigation of the external leakage in NP8320 solenoid valves (Ref A), ASCO has identified an additional group of valves which could be potentially susceptible to such leakage. The initial review focused on our standard NP8320 products and did not include our special construction valves. However, we expanded our review to include all special as well as standard NP8320 valves. As a result, the quantity of potentially affected valves has increased from 174 to 438. In response to this new information, revised notices were sent to the original customers and the newly identified customers: ASCO Canada, SPX Industries, and Flowserve.

"As of this date, 115 valves have been returned. None of these returned valves has exhibited external leakage when retested per the updated procedure."

Through their expanded review process, ASCO did not identify any additional commercial nuclear power plant customers which had purchased valves susceptible to the leakage issue.

Notified R4DO (Gaddy) and Part 21 Group via e-mail.

AGREEMENT STATE REPORT INVOLVING AN EXIT TRITIUM SIGN DESTROYED IN A FACILITY FIRE

The following information was received by facsimile:

"The RPS [North Carolina Radiation Protection Section] received a voice message on 1-6-2011 from the FMC Lithium RSO [Radiation Safety Officer]. The RSO wanted RPS to contact him concerning removing an Exit Sign from his current inventory of sources. [RPS] was able to get in touch with the RSO on Wednesday, January 12, 2011 and the RSO stated on the phone than he needed to remove the Exit Sign because there was a fire at the facility on September 18, 2010 that shut down the facility for two weeks and damage was around $500,000. RPS explained to the RSO that he should have responded and reported the incident/fire immediately to our office.

"[RPS] received a call back from the RSO for FMC Lithium concerning which Exit Sign was affected by fire on September 18, 2010. The General License Number: 036-2384-0G has 6 Cs-137 gauges that are active and one Cs-137 gauge in storage. Also, they have 22 Tritium exit lights in service on and before the fire on September 18, 2010. The reason the RSO reported the Exit Sign on 1-12-2011 was he was going to order a replacement for the one that was destroyed in the fire and he was getting ready to perform a Radiation Training Session for their employees. The source that was destroyed was: Manufacturer: Shield, Model: SLX-60, Serial Number: 10-21664, Source: H-3, Activity: 0.230 mCi ea., Location: SO Building 1st floor. Installed: Aug/2010"

North Carolina Event: 11-02

* * * UPDATE FROM WILLIAM JOHNSON TO JOE O'HARA AT 1246 EST ON 1/18/11 * * *

The state called to clarify that the activity level is 6.21 Curies H-3 vice 0.230 mCuries, and the manufacturers full name is Shield/Isolite vice Shield as reported above for the exit sign which was destroyed.

Notified R1DO(Jackson) and FSME(Villamar).

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

UNUSUAL EVENT DECLARED DUE TO HIGH-HIGH REACTOR BUILDING SUMP LEVEL ALARM

"This is a one-hour report for the discovery of a condition that met an Emergency Activation Level (EAL) for a Notification of an Unusual Event [NOUE].

"EAL HU-1 - Natural and Destructive Phenomena Affecting the Protected Area Threshold Value 6 states, 'Exceed Max Normal Operating Values specified in EOP 31 EO-EOP-014-1 SC - Secondary Containment Control Table 5 Secondary Containment Operating Water Levels.'

"Plant Hatch Unit 1 declared a NOUE on 9/18/10 at 1627 based on HU-1 Natural and Destructive Phenomena Affecting the Protected Area due to exceeding the Max Normal Operating Value for the Reactor Building NE Diagonal Floor Drain Sump. At 1615, both the Level High and Level High-High annunciators alarmed. Water has not overflowed the sump. However, due to its design, it is not possible to immediately visually confirm the sump level. The sump pumps were not running and would not run with their switches in START indicating either: (1) there is no water in the sump, (2) both pumps are OOC [Out of Commission], or (3) there is a problem in the sump level control system. Maintenance is assessing the situation."

The licensee has notified the state and local agencies and will notify the NRC Resident Inspector.

* * * UPDATE FROM STEVE BURTON TO HOWIE CROUCH @ 0427 EDT ON 9/19/10 * * *

At 0400 EDT, the NOUE was terminated. The termination criteria was that the NE Diagonal Floor Drain Sump level was in its normal operating range with no abnormal sump in-leakage detected. Compensatory measures are in place to measure level in the sump. An investigation into the abnormal level indication is still in progress.

The licensee will be notifying state and local authorities as well as the NRC Resident Inspector. Notified R2DO (Henson), IRD (Gott), NRR EO (Howe), DHS (Inser) and FEMA (Via).

* * * RETRACTION FROM STEVE BURTON TO JOE O'HARA AT 1533 EDT ON 10/7/10 * * *

"On September 18, 2010, a notification, Event Number 46258, was submitted to the NRC to report a circumstance at Plant Hatch Unit 1 which appeared to be a 'High-High' reactor building sump level alarm. Such an alarm would meet the designated Emergency Activation Level (EAL) for a Notification of an Unusual Event (NOUE). On the day of the event, it was thought that receipt of both the 'High' and 'High-High' level annunciators for the reactor building northeast diagonal floor drain sump was indicative of the sump level having reached its maximum normal operating level, and a NOUE was made.

"During a subsequent Investigation, engineering personnel determined that the 'High' and 'High-High' level switches for this sump are wired such that both alarms are actuated concurrently when the 'High' level in the sump is reached at approximately 52 Inches. The 'High-High' sump level annunciation (the level at which the NOUE must be made) Is supposed to alarm at approximately 60 inches. Engineering personnel also determined that the level logic is currently improperly configured to clear both the 'High' and 'High-High' level alarms when the sump level rises to 60 inches.

"The initial 'High' and 'High-High' level alarms in the main control room were received at approximately 1615 EDT on September 18, 2010. At that time the sump level would have reached an actual level of approximately 51 inches (albeit with a false indication of approximately 60 inches due to the configuration error noted above) based on the setpoint at which this alarm occurs. The normal leakage into this sump at the time of this event was at a rate of approximately 1 inch per hour. The sump pumps were started at approximately 1800 EDT to pump down the sump. This action resulted in a maximum actual sump level of approximately 53.5 inches, assuming the normal leakage into the sump was occurring during this period. At no time did the sump level actually reach the 'High-High' sump level criteria of 60 inches, nor did the annunciated level clear prior to pumping down the sump which also demonstrated that the 60 inch criteria was not met.

"It is now apparent that the initial NOUE was a conservative report that was properly made based on the information available to the operators at the time. The subsequent investigation provided additional information regarding actual sump level conditions including information that both 'High' and 'High-High' alarms annunciate at the 'High' sump level and would have cleared had the 'High-High' level been reached. Since the 'High-High' sump maximum normal operating level of 60 inches was never reached during this event, the determination has been made that the EAL was not appropriate given the actual sump conditions, thereby making the event non-reportable and an NOUE unnecessary.

"Based on the preceding Information, Southern Nuclear Company (SNC) hereby provides notification that Event Number 46256 is retracted."

The licensee will notify the NRC Resident Inspector.

Notified R2DO(McCoy).