Event Notification Report for February 22, 2012

MANUAL REACTOR SCRAM DUE TO HIGH DELTA-P ACROSS CIRCULATING WATER PUMP TRAVELING SCREENS

"At 2319 hours EST, a manual Reactor Protection System (RPS) actuation was inserted on Unit 1 in anticipation of a loss of condenser vacuum. Shortly before the manual RPS actuation, Circulating Water Intake Pump (CWIP) 1B tripped due to high delta-pressure across the intake traveling screen. This caused the trip of the remaining pumps. Previously, at 1859 hours, balance of plant (BOP) bus Common C unexpectedly de-energized. This caused loss of power to the CWIP traveling screen motors which, in turn, lead to the high delta-pressure across the traveling screen(s).

"All control rods inserted properly. As a result of the scram, reactor water level reached the Low Level 1 actuation set point and Primary Containment (i.e., Group 6) isolation occurred. All systems functioned as designed. The High Pressure Coolant Injection (HPCI) system is being used, as needed, for pressure control. The Reactor Core Isolation Cooling (RCIC) system is being used, as needed, for level control. No Safety/Relief Valves (SRVs) actuated as a result of the manual RPS actuation.

"The manual RPS actuation is reportable in accordance with 10CFR50.72(b)(2)(iv)(B) and 10CFR50.72(b)(3)(iv)(A). The actuation of the HPCI and RCIC systems and the Group 6 isolation are reportable in accordance with 10CFR50.72(b)(3)(iv)(A)."

The unit is currently in Mode 3 with a cooldown in progress.

The licensee notified the NRC Resident Inspector. Notified R2DO (Ernstes).

* * * UPDATE FROM STEWART BYRD TO CHARLES TEAL AT 0741 EST ON 2/23/12 * * *

"At 2319 hours EST, a loss of all Circulating Water Intake Pumps caused a lowering vacuum on Unit 1. As previously reported (i.e. Event Notification 47690), a manual Reactor Protection System (RPS) actuation was inserted on Unit 1 at this time. In addition, a valid actuation of the RPS, High Pressure Coolant Injection (HPCI), Reactor Core Isolation Cooling (RCIC), and a Group 6 isolation was reported in accordance with 10CFR50.72(b)(3)(iv)(A). At 2342, Main Condenser vacuum was 15 in. Hg and lowering. All Main Steam Isolation Valves were slow closed in anticipation of Group 1 isolation at this time. This follow-up notification is being made to report the manual actuation of the Group 1 isolation valves in accordance with 10 CFR 50.72(b)(3)(iv)(A). The Group 1 isolation was discussed with the NRC during initial notification of EN 47690, and this follow-up is providing written notification of the MSIV closure."

The NRC Resident Inspector has been notified. Notified R2DO (Ernstes).

AGREEMENT STATE REPORT - STUCK GAUGE SHUTTER

The following information was received via facsimile:

"On February 22, 2012, the State of Texas was notified by the licensee that the shutter on an Ohmart SH-F1A nuclear gauge containing 50 millicuries of cesium 137 was found stuck in the open position. The gauge shutter was being closed to reduce dose rates in an area where calibration of equipment was to be done. Open is the normal position for the gauge and the gauge does not create any additional exposure risk to any individual. The licensee is making arrangements with the manufacturer for repairs to the gauge. Additional information will be provided as it is received in accordance with SA-300."

Texas Incident #: I-8936

ELECTRICAL DISTRIBUTION SYSTEM MAINTENANCE TO IMPACT EMERGENCY RESPONSE FACILITIES

"Calvert Cliffs will be performing planned U-1 Refueling Outage maintenance to a portion of the sites 1E Electrical Distribution System. This maintenance window is expected to be 36 hours long and will start at 1400 today. This will impact the dissemination of plant data to the TSC, EOF, and OSC. ERDS will also be out of service for both Unit-1 and Unit-2. Should an emergency be declared during this period, the Control Room will continue to have the capability to retrieve plant data inputs to assess plant conditions and perform core damage assessment.

"Control Room Emergency Response Organization personnel will use backup methods already captured in emergency response procedures to disseminate plant parameter data to the effected Emergency Response Facilities and NRC during the plant data network outage. MIDAS (Meteorological Data) will continue to be operational at the site."

The licensee notified the NRC Resident Inspector.

UNANALYZED CONDITION RELATED TO CERTAIN POSTULATED FIRE CONDITIONS

"At 1307 CST on February 22, 2012, it was identified that under certain fire conditions, the ability to meet the performance criteria of the approved fire protection program may be challenged. Specifically the cabling for Train A Pressurizer Power Operated Relief valve and Train B Pressurizer Power Operated Relief valve alternate circuits may be affected under certain fire conditions affecting the relay room. The ability to maintain pressurizer level within the indicated range may be challenged due to a spurious opening of a pressurizer power operated relief valve during these postulated conditions.

"Compensatory actions to address the fire in the area of concern are in place. This condition is reported pursuant to 10CFR50.72(b)(3)(ii)(B).

"A similar condition was previously reported [by the licensee] in EN #44482. The compensatory measures that had been put in place for that earlier condition remain applicable to this current condition."

The licensee notified the NRC Resident Inspector.

TECHNICAL SPECIFICATION REQUIRED SHUTDOWN DUE TO INOPERABILITY OF EMERGENCY CORE COOLING SYSTEMS

"At 1859 hours EST, the Brunswick site experienced a loss of balance of plant (BOP) bus Common C. As a result, makeup pumps to the ECCS discharge line keepfill systems lost power. At 1905 on Unit 1, 'A' loop of the Core Spray (CS) system received a low discharge pressure alarm and was declared inoperable. At 1916 hours, 'B' loop of the Residual Heat Removal (RHR) system received a low discharge pressure alarm and was declared inoperable. With the loss of the second low pressure ECCS system, Condition J of Technical Specification 3.5.1, 'ECCS Operating,' was entered, which requires the Unit 1 to enter LCO 3.0.3 immediately. At 1931 hours, 'A' loop of RHR was declared inoperable due to low discharge pressure. Power reduction of Unit 1 was initiated at 2014 hours.

"At 2055 hours on Unit 2, 'A' loop of the Residual Heat Removal (RHR) system received a low discharge pressure alarm and was declared inoperable. At 2128 hours, 'B' loop of the Core Spray (CS) system received a low discharge pressure alarm and was declared inoperable. With the loss of the second low pressure ECCS system, Condition J of Technical Specification 3.5.1, 'ECCS Operating,' was entered, which requires the Unit 2 to enter LCO 3.0.3 immediately. Power reduction of Unit 2 was initiated at 2219 hours.

"This event reportability is in accordance with 10CRF50.72(b)(2)(i), Technical Specification Required Shutdown, due to inoperability of ECCS systems.

"The initial safety significance of this event is minimal. Offsite power and the Emergency Diesel Generators are operable. The High Pressure Coolant Injection (HPCI) system remains operable on both Unit 1 and Unit 2. The Reactor Core Isolation Cooling (RCIC) system remains operable on Unit 1 and is being restored following maintenance on Unit 2.

"Troubleshooting activities to determine the loss of the BOP Common C bus are in progress. Efforts are in progress to install temporary power to the keepfill makeup pumps."

The licensee will notify the NRC Resident Inspector.


* * * UPDATE FROM CURTIS DUNSMORE TO DONALD NORWOOD AT 0223 EST ON 2/23/2012 * * *

"Unit 1 - At 2315 hours, temporary power was provided to the ECCS keepfill makeup pump and the ECCS systems were restored. LCO 3.0.3 was exited on Unit 1 at 0041 hours with restoration of the 'A' and 'B' loops of the RHR systems. The 'A' loop of the Core Spray system was restored at 0058 hours on 2/23/2012."

During the shutdown, Unit 1 was manually scrammed due to high delta-pressure across the Circulating Water Pump traveling screens. See EN #47690 for details.

"Unit 2 - At 2315 hours, temporary power was provided to the ECCS keepfill makeup pump and the ECCS systems were restored. LCO 3.0.3 was exited on Unit 2 at 2354 hours with restoration of 'B' loop of the RHR system. The 'A' loop of the Core Spray system was restored at 0039 hours. Unit 2 was at 96% of Rated Thermal Power when the shutdown was terminated."

The licensee notified the NRC Resident Inspector. Notified R2DO (Ernstes).

SUSPICIOUS PACKAGE DISCOVERED ON SITE

"The following event description is based on information currently available. If through subsequent reviews of this event additional information is identified that is pertinent to this event or alters the information being provided at this time a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73

"At 1852 hours, Palo Verde Unit 1 was notified of a suspicious package located in the Owner Controlled Area outside the Protected Area. Maricopa County Sheriff's Office was contacted for assistance with a bomb disposal unit. Local media has become aware of this event and expressed interest by dispatching helicopters and television crews.

"There are no safety systems impacted by the package and operations personnel are not hampered in their ability to operate safety related equipment. There is no release of radioactivity to the environment as a result of this package and it has not adversely affected the safe operation of the plant or health and safety of the public. All three Palo Verde units are being maintained stable at approximately 100% power.

"The NRC Resident Inspector has been notified."

* * * UPDATE FROM DELBERT ELKINTON TO VINCE KLCO ON 2/24/12 AT 1619 EST * * *

"The Maricopa County Sherriff's Office bomb disposal unit responded and inspected the package. The suspicious package contained a granular absorbent material, similar to that used to clean liquid spills. The event was terminated at 23:02 AZ MST [on 2/22/12]. The NRC Resident Inspector has been updated."

Notified the R4DO (Deese).