Event Notification Report for July 13, 2005

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
THIS IS NOT A NEW REPORT.

This event report was originally withheld from public release under the NRC's policy for protecting sensitive unclassified information. The NRC has reevaluated this policy and is now making this event report available to the public with suitable redactions.
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

FIRE ALARM COMMUNICATION SYSTEM FAILURE

"On Wednesday, July 13, 2005, at approximately 9:40 pm, NPD established a storm watch for the facility criticality alarm system during a violent thunderstorm. At approximately 9:50 pm, a lightning strike at the Mt. Athos facility activated the criticality monitoring system and damaged the fire alarm system.

"Storm watch procedures were in place and personnel were evacuated to a safe location. After repairs were complete, at approximately 1:00 am, during functional testing of the [DELETED] criticality alarm system, a power surge occurred. Tests indicated that while the [DELETED] facility safety alarms were functional, communications from the alarm panel, which includes the fire alarms to the NPD [DELETED] Alarm Station [DELETED], were lost. It is uncertain whether the lightening strike or the power surge damaged the communications capability.

"By 9:00 am on July 14, 2005 the system was repaired and fire detection was functional."

"Evaluation of the Event:

"10 CFR 70.50(b)(2) states that the NRC must be notified of an event within 24 hours followed by a 30-day written report if the following condition is met. An event in which equipment that meets all of the following three conditions is disabled or fails to function as designed: [10CFR70.50(b)(2)]

"(1) The equipment is required by regulation or license condition to prevent releases exceeding regulatory limits, to prevent exposures to radiation and radioactive material exceeding regulatory limits, or to mitigate the consequences of an accident and

"(2) The equipment is required to be available and operable when it is disabled or fails to function; and

"(3) No redundant equipment is available and operable to perform the required safety function.

"License SNM-42, Chapter 1, Section 1.9.2 requires that: 'Fire detectors be installed and maintained in controlled areas. These detectors will alarm in the continuously manned NPD [DELETED] alarm station.' The system malfunction prevented the [DELETED] controlled area fire detection from alarming in the NPD [DELETED] alarm station.

"Evaluations have been performed to determine that the fire detection system in this area is not an IROFS and that regulatory limits will not be exceeded by a fire.

"The equipment was required to be available and operable when it failed to function. Also, redundant equipment was not available; however, compensatory measures were utilized. Radiation Protection personnel were dispatched to monitor the local alarms and system activations. Compensatory measures [personnel at the local alarm panel] were in place by approximately 1:00 am.

"Notification Requirements

"The event is reportable due to:

"Although the fire system monitoring is not an IROFS, it is required by the license to mitigate the consequences of an event in a controlled area. Also, it was required to be functional when the communications loss occurred and a redundant system was not available to perform the required safety function. Based on this, notification is required to the NRC within 24 hours followed by a 30-day written report.

"Status of Corrective Actions:

"The system has been repaired, tested, and is functioning properly. A new surge protector will be installed on the Honeywell System when it is received."

The licensee notified the NRC Resident Inspector.

* * * UPDATE ON 05/11/08 BY H. Crouch * * *

THIS IS NOT A NEW REPORT.

This event report was originally withheld from public release under the NRC's policy for protecting sensitive unclassified information. The NRC has reevaluated this policy and is now making this event report available to the public with suitable redactions.
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
THIS IS NOT A NEW REPORT.

This event report was originally withheld from public release under the NRC's policy for protecting sensitive unclassified information. The NRC has reevaluated this policy and is now making this event report available to the public with suitable redactions.
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

EMERGENCY DECLARED DUE TO CRITICALITY ALARMS

At 2230 EDT the facility received multiple Criticality Alarms believed to be due to lightning strikes on site. The Emergency Operations Center has been activated and is in the process of staffing. Most alarms have been reset to normal. The licensee has sent teams to take local radiation readings. Local state and local agencies have been notified. The NRC Resident Inspector has been notified and is onsite.

* * * UPDATE FROM POWELL TO ROTTON AT 2330 ON 07/13/05 * * *

BWXT secured Alert based on surveys of affected areas being normal.

* * * UPDATE FROM POWELL TO GOTT AT 0010 ON 07/14/05 * * *

"Emergency has been terminated. EOC will maintain a minimal staffing for follow-up. A Post Incident Review Team has been appointed to assess the incident."

* * * UPDATE AT 0026 ON 17/14/05 * * *

NRC secured monitoring.

Notified R2 IRC (Plisco, D. Collins), R4DO (B. Spitzberg), IRD (Wilson), NMSS (Strosnider, Gillen). Commission Staff (Castleman, Thoma, Hatchett, Piccone), EDO/EDO staff (Virgilio, Dyer, Kane, Miller), IRD (Wilson, Leach, McGinty), PAO (Brenner), DOC (Outlaw), DHS (S. York), FEMA (Dunker), DOE (Bailey), EPA(NRC) (Allison), HHS (White).

* * * RETRACTION AT 0959 ON 07/15/05 FROM L. MORRELL TO W. GOTT * * *

"On Wednesday, July 13, 2005, at 10:45 p.m. BWX Technologies, Inc. declared an Alert per the BWXT Emergency Plan and internal emergency procedures. BWXT contacted the NRC Operations Center to report that an Alert had been declared due to a criticality alarm that resulted from a lightning strike. The decision to declare an Alert was based on the fact that radiation indicator alarms on the criticality panel went into a high alarm and it was not immediately determined that high radiation levels did not exist. EOC personnel conservatively determined that an Alert should be declared and implemented the notification process while an evaluation into the exact cause of the alarm was implemented. Further evaluation of the situation confirmed that the activation of the alarms was not caused by high levels of radiation but by the lightning strike, which caused damage to electronic components within the alarm system. Therefore, the Alert criteria were actually not met. BWXT is requesting that the Alert declaration that was made on July 13, 2005, be withdrawn."

The licensee notified the NRC Resident Inspector.

Notified R2DO (P. Fredrickson) and NMSS (S. Moore).

* * * UPDATE ON 05/11/08 BY H. Crouch * * *

THIS IS NOT A NEW REPORT.

This event report was originally withheld from public release under the NRC's policy for protecting sensitive unclassified information. The NRC has reevaluated this policy and is now making this event report available to the public with suitable redactions.
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

TURBINE TRIP/REACTOR TRIP

"On July 13, 2005, at approximately 0917 hours, Unit 1 received a Reactor Protection System (RPS) trip and a Main Turbine trip. All control rods fully inserted into the core. Plant response to the reactor shutdown resulted in a reactor coolant level transient that caused a Low Level 2 signal and subsequent High Pressure Coolant Injection (HPCI) system initiation. The HPCI system started but did not inject into the vessel because reactor coolant level was already recovered by the Reactor Feedwater system. Proper operation of the RCIC system has not been conclusively determined. Both Reactor Recirculation pumps tripped, as expected, from the low reactor coolant level and high pressure transient.

"Additionally, primary containment isolation system actuation signals for valve groups 2, 3, 6, and 8 were received and the valves, that were open, closed as required. The Reactor Building Ventilation System isolated and both trains of the Standby Gas Treatment (SBGT) System automatically started and operated successfully.

"The RPS trip was reset and the HPCI turbine secured. Both trains of the SBGT system were secured. At 1119 hours, the plant exited the scram recovery procedure and entered General Plant Operating procedure 0GP-05, "Unit Shutdown." Investigation into the cause of the RPS and Main Turbine trip is still in progress.

"The plant is currently in Mode 3 (i.e., Hot Shutdown) and activities are in progress to transition to Mode 4 (i.e., Cold Shutdown). The resident inspector has been notified.

"INITIAL SAFETY SIGNIFICANCE EVALUATION

"The initial safety significance of this condition is considered to be minimal. The plant responded as designed to the transient, with the exception of the verification of RCIC system performance, and the plant was safely shut down.

"CORRECTIVE ACTIONS

"An event investigation team has been assembled to determine the cause of the event. Plant response to the event is being evaluated and identified issues will be addressed prior to plant restart."

During the transient, four safety relief valves lifted and reset. The plant is currently in a normal shutdown electrical lineup. Reactor vessel level is being maintained using normal feedwater. The bypass valves are available for cooldown. There was no effect on unit-2.


* * * UPDATE FROM LICENSEE TO ABRAMOVITZ AT 1741 ON 7/14/05 * * *

"On July 13, 2005, at approximately 0917 hours, Unit 1 received a Reactor Protection System (RPS) trip and a Main Turbine trip. All control rods fully inserted into the core and the plant safely shut down. A non-emergency notification (Event Number 41837) was made to the NRC Operations Center at 1303 hours. This follow-up notification discusses plant recovery from the Unit 1 event.

"After investigation team review of plant data, it was determined that the RCIC system performed appropriately (i.e., was not required to start) in response to the reactor coolant level transient. Reactor coolant level decreased to near, but did not exceed, the RCIC System actuation instrumentation setpoint. The investigation team determined that the direct cause of the RPS/Main Turbine trip is the shorting to ground of one phase of the Unit 1 Main Generator No-Load Disconnect Switch, which electrically connects the generator to the Main Transformer. The switch grounding caused a generator ground fault that resulted in a backup generator lockout and fast closure of the turbine control valves. Fast closure of the turbine control valves provided the trip input to the RPS.

"Unit 1 is now making preparations to go to mode 4, cold shutdown. Unit 1 and Unit 2 are currently in Technical Specification (TS) Limiting Condition for Operation (LCO) 3.8.1 'AC Sources - Operating,' for one of two required Unit 1 offsite AC circuits inoperable. The resident inspector has been notified.

"CORRECTIVE ACTIONS

"Further testing of RCIC System Low Reactor Level actuation instrumentation will be performed to further verify satisfactory RCIC System performance during the event. Activities are in progress to address the damaged No-Load Disconnect Switch and to determine the cause of the switch failure."

Notified the R2DO (Fredrickson).

DAMAGED MOISTURE DENSITY GAGE

A CPN moisture density gage was run over at a job site. The source was retracted during the event. There is damage to the handle . The sources are intact (0.4 mR/hr @ 1 meter). The gage is being sent to the manufacturer for repairs.

Serial number: ND90404949
Model number: MC1DRP
Sources: Cs-137 10 milliCurie
Am-241:Be 50 milliCurie