Event Notification Report for June 12, 2012

SAFETY EQUIPMENT FAILURE - CRITICALITY AIR HORNS NOT TESTED FOR AUDIBILITY

"While reviewing Maintenance Work Package 'Performance of the C-335 Annual CMS Surveillance' from April 28, 2012 an error was identified. Procedure 'C-335 CMS Maintenance And Testing' requires an audibility check if the as-found values for the regulator air pressure drift feeding the Criticality Accident Alarm System (CMS) air horns is >?12 psig. However, an audibility check was not performed as required at six locations all on the cell floor of the process building that were discovered to be out-of-tolerance. All air pressure regulators were adjusted to within acceptable-as-left tolerances prior to the system being made operable on April 28.

"Without the audibility testing being performed, the audibility of the C-335 CMS was questionable prior to the April testing. On June 13, 2012, a work package was developed to recreate the pressures encountered on April 28 and to test the audibility of the CMS. Subsequent testing has shown that three of the CMS horns fed by out-of-tolerance pressure regulators may not have provided the required sound levels necessary for audibility in those areas. This is failure of safety equipment required by TSR 2.4.4.2.

"This event is reportable as a 24 hour event in accordance with 10 CFR 76.120(c)(2), 'An event in which equipment is disabled or fails to function as designed when: (i) the equipment is required by a TSR to prevent releases, prevent exposures to radiation and radioactive materials exceeding specified limits, mitigate the consequences of an accident, or restore this facility to a pre-established safe condition after an accident; (ii) the equipment is required by a TSR to be available and operable and either should have been operating or should have operated on demand; and (iii) no redundant equipment is available and operable to perform the required safety function.'

"The NRC Resident Inspector has been notified of this event.

"PGDP Assessment and Tracking Report No. ATRC-12-1496; PGDP Event Report No. PAD-2012-03; Responsible Division: Operations"

* * * RETRACTION FROM BILLY WALLACE TO JOHN SHOEMAKER AT 1641 EDT ON 07/16/2012 * * *

"Subsequently, the C-335 CAAS air horns have been tested in the as-found conditions from April 28, 2012. Using the original design audibility criteria in the most limiting condition, the CAAS horn audibility was found to be acceptable. Therefore, the system would have been able to perform its intended safety function in the April 28, 2012, as-found condition. Based on the testing and an engineering evaluation, the event notification is being retracted."

The licensee has notified the NRC Resident Inspector.

Notified R2DO (Calle) and NMSS (Silva).

TECHNICAL SUPPORT CENTER TAKEN OUT OF SERVICE FOR MAINTENANCE

"On June 12, 2012, at approximately 1121 hours [CDT], the Kewaunee Power Station Technical Support Center (TSC) ventilation system was removed from service to allow TSC electrical distribution system repairs. The removal of the ventilation system potentially affects the TSC habitability during a declared emergency requiring activation. The Emergency Response Organization [ERO] team has been notified of the maintenance and the possible need to relocate during an emergency. If an emergency is declared and TSC ERO activation is required, the TSC will be staffed and activated unless the TSC becomes uninhabitable due to ambient temperatures, radiological, or other conditions. If relocation of the TSC staff becomes necessary, the Station Emergency Director will relocate the staff to an alternate TSC location.

"The ventilation system is expected to be out of service for approximately 2 hours.

"This condition is being reported in accordance with 10CFR50.72(b)(3)(xiii) as an event that resulted in a major loss of emergency assessment capability.

"The NRC Resident Inspector has been notified."

TSC work was completed and the TSC was returned to service at 1326 CDT.

TECHNICAL SPECIFICATION REQUIRED SHUTDOWN

"At 1456 hours on June 12, 2012, the plant commenced a shutdown due to water leakage from the SIRW [Safety Injection Refueling Water] tank exceeding the operational decision-making issue process trigger point of 31 gallons per day causing it to be declared inoperable and requiring entry into Technical Specification (TS) 3.5.4, Condition B. TS 3.5.4 Condition B requires the SIRW Tank to be returned to operable status within one hour or entry into Condition C that requires the plant to be in Mode 3 within 6 hours and Mode 5 within 36 hours.

"Actual leakage from the SIRW Tank was measured at approximately 31.4 gallons per day. This event had no impact on the health and/or safety of the public.

"The NRC Senior Resident Inspector has been notified."

The licensee believes that the tank is leaking from several locations. However, at this time, they cannot determine exact locations. The refueling water has minor tritium contamination. The refueling water is being collected in a reservoir and then pumped into a holding tank. The licensee will be shutting down to cold shutdown.

* * * RETRACTION ON 8/7/12 AT 1219 EDT FROM TERRY DAVIS TO DONG PARK * * *

"Subsequent review concluded the condition did not meet reporting criteria. The rate of water leakage from the Safety Injection Refueling Water Tank had reached an administrative limit. Shutdown was not required by the Technical Specifications. The plant shutdown commenced in accordance with normal plant operating procedures. At 1849 hours on June 12, 2012, the reactor was manually tripped. This event is not reportable as the reactor trip was part of a normal shutdown for corrective maintenance. Mode 5 was reached at 1745 hours on June 13, 2012. The NRC Resident Inspector has been notified."

Notified R3DO (Lipa).

LOSS OF THE PLANT PROCESS COMPUTER SYSTEM

"At 1757 EDT on 6/12/12, Brunswick Nuclear Plant experienced a fault on the Emergency Response Facility Information System (ERFIS) uninterruptible power supply (UPS) electrical bus 'A'. This resulted in a loss of site Safety Parameter Display System (SPDS), Emergency Response Data System (ERDS) and Plant Process Computer (PPC) for both Unit 1 and Unit 2. The cause of the fault is not yet understood and under investigation. No other major plant effects occurred and no major plant evolutions are planned.

"During the loss of SPDS, the emergency response capability of that system was lost to the site. During the loss of ERDS, the automatic data transfer feature of that system was lost for transmissions to the NRC, however manual data transfer is still available. During the loss of the PPC, automatic core thermal power averaging and automatic core thermal limit monitoring was lost. Manual calculations are available for these functions.

"Unit 1 SPDS was restored to the Emergency Operations Facility (EOF) at 1949 EDT. Unit 2 SPDS was restored to the EOF at 2030 EDT. ERDS and PPC remain unavailable with troubleshooting in progress. Both units reduced power to 98% as a conservative measure.

"The NRC Resident Inspector has been notified."

* * * UPDATE FROM JOHN MILLER TO JOE O'HARA AT 0257 ON 6/14/12 * * *

"The Unit 1 and 2 ERFIS, SPDS, and ERDS functions were restored by approximately 0630 hours on June 13, 2012, after an alternate power supply configuration was established. In addition, the PPC functions were restored by approximately 1630. Compensatory actions will be maintained until the UPS 'A' bus is restored and returned to normal configuration. The Brunswick Emergency Response Organization (ERO) Site Emergency Coordinator and Emergency Response Manager have been briefed on the compensatory actions in place.

"Investigation of this condition will be documented in the corrective action program in Condition Report (CR) 542704.

"The NRC Resident Inspector was notified."

Notified R2DO(Ayres)