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Event Notification Report for September 10, 2010

U.S. Nuclear Regulatory Commission
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Event Reports For
09/09/2010 - 09/10/2010

** EVENT NUMBERS **


46237 46238 46240 46241

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General Information or Other Event Number: 46237
Rep Org: ROTORK CONTROLS
Licensee: ROTORK CONTROLS
Region: 1
City: ROCHESTER State: NY
County:
License #:
Agreement: Y
Docket:
NRC Notified By: PATRICK A. SHAW
HQ OPS Officer: VINCE KLCO
Notification Date: 09/09/2010
Notification Time: 14:36 [ET]
Event Date: 07/16/2010
Event Time: [EDT]
Last Update Date: 09/09/2010
Emergency Class: NON EMERGENCY
10 CFR Section:
21.21 - UNSPECIFIED PARAGRAPH
Person (Organization):
ROBERT HAAG (R2DO)
PART 21 VIA EMAIL ()

Event Text

PART 21 REPORT FOR AN OPTIONAL SUBASSEMBLY USED ON VALVE ACTUATORS

The following information was received by facsimile:

"Rotork designs and manufactures valve actuators; a product that attaches to a valve to permit the remote operation of the valve.

"[Rotork Controls] is writing to notify the NRC that Duke Energy has received from Rotork a basic assembly containing a defective sintered gear Pt. No. 22641. No other [NRC] licensee has received this part. The defective component is part of an optional subassembly called an 'Add On Pack' (AOP). Duke Energy purchased AOPs with all Rotork NA1E type actuators.

"The defective gear could cause the AOP to seize and fail to operate. The actuator will continue to perform its safety related function with a seized AOP. The AOP provides position information, through auxiliary switches, during the actuator's operation.

"Duke Energy was first notified of the condition on July 16, 2010 and on August 6, 2010 received a formal letter in which the extent of condition was communicated. Rotork proceeded to investigate the problem, run life tests and understand the failure mode. On September 3, 2010 Duke Energy informed Rotork in writing that the AOP must support the design-basis function of the associated valve/actuator assembly. On the same date Rotork shared with Duke energy [information] which confirmed that the gear design was sound and that the gear failure was attributable to the supplier's manufacturing process.

"The gear supplier's production process has been corrected and Rotork quality assurance is verifying that subsequent batches are conformant to specification. Duke Energy is being provided with replacement AOPs and conformant gears on an as requested basis."

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Power Reactor Event Number: 46238
Facility: ROBINSON
Region: 2 State: SC
Unit: [2] [ ] [ ]
RX Type: [2] W-3-LP
NRC Notified By: GARRETT SANDERS
HQ OPS Officer: DONALD NORWOOD
Notification Date: 09/09/2010
Notification Time: 18:04 [ET]
Event Date: 09/09/2010
Event Time: 14:37 [EDT]
Last Update Date: 09/09/2010
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL
50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Person (Organization):
ROBERT HAAG (R2DO)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
2 A/R Y 100 Power Operation 0 Hot Standby

Event Text

REACTOR TRIP DUE TO OVERTEMPERATURE DELTA-T SIGNAL

"At 1437 hours EDT on September 9, 2010, with the unit in Mode 1 at 100% power, an automatic reactor trip occurred. The reactor trip signal was based on the Overtemperature Delta-T reactor protection function.

"During the event, the steam generator power operated relief valves (PORVs) and one pressurizer PORV briefly opened and re-closed, in response to pressure changes in the steam generators and pressurizer due to the plant transient condition. The Auxiliary Feedwater System automatically actuated, as expected, and provided feedwater to the steam generators. The main steam safety valves did not open during the event. All control rods indicated fully inserted following the reactor trip.

"The normal post-trip electrical lineup is providing power to the plant and the electrical system is stable. Decay heat is being removed via the condenser. The reactor is currently stable in Mode 3.

"There was an indication of an approximate 0.65 gpm leak to the pressurizer relief tank following the reactor trip. The isolation valve to the pressurizer PORV that opened during the reactor trip was closed and the leak indication stopped. The indicated leakage was within Technical Specification leakage rate limits.

"The cause of the reactor trip and indication of pressurizer PORV leakage is under investigation."

The licensee notified the NRC Resident Inspector.

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Power Reactor Event Number: 46240
Facility: POINT BEACH
Region: 3 State: WI
Unit: [1] [2] [ ]
RX Type: [1] W-2-LP,[2] W-2-LP
NRC Notified By: JAMIE WEIGANDT
HQ OPS Officer: VINCE KLCO
Notification Date: 09/09/2010
Notification Time: 20:25 [ET]
Event Date: 09/09/2010
Event Time: 16:20 [CDT]
Last Update Date: 09/09/2010
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(xi) - OFFSITE NOTIFICATION
Person (Organization):
CHRISTINE LIPA (R3DO)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
1 N Y 100 Power Operation 100 Power Operation
2 N Y 100 Power Operation 100 Power Operation

Event Text

EMERGENCY SIRENS INADVERTENTLY ACTUATE

"At 1520 [CST], Point Beach was notified by Manitowoc County Sheriff's Department (MCSD) and citizens of audible EP Siren actuation in the City of Two Rivers and the Town of Two Creeks, WI. System troubleshooting was in progress at the time of actuation.

"Alert and Notification System Siren configuration was restored to normal at approximately 1630 [CST]. All required ANS sirens were 'Poll tested' and are fully functional.

"Further reviews indicated that Sirens P-001 through P-013 (13 sirens) had each simultaneously received a 180 second activation. At this time the cause of the activation signal is unknown. All troubleshooting and testing are currently suspended; event investigation has commenced."

The licensee notified the NRC Resident Inspector.

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Power Reactor Event Number: 46241
Facility: INDIAN POINT
Region: 1 State: NY
Unit: [ ] [3] [ ]
RX Type: [2] W-4-LP,[3] W-4-LP
NRC Notified By: DON DEWEY
HQ OPS Officer: HOWIE CROUCH
Notification Date: 09/10/2010
Notification Time: 00:29 [ET]
Event Date: 09/09/2010
Event Time: 21:29 [EDT]
Last Update Date: 09/10/2010
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL
50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Person (Organization):
WILLIAM COOK (R1DO)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
3 M/R Y 100 Power Operation 0 Hot Standby

Event Text

MANUAL REACTOR TRIP DUE TO SERVICE WATER LEAK IN THE MAIN GENERATOR EXCITER HOUSING

"On September 9, 2010, at approximately 2129 hours [EDT], Indian Point 3 manually tripped the reactor from the control room following indications of a service water leak in the Main Generator Exciter housing. Unit 3 is currently stable in mode 3. All automatic actions occurred as required. All control rods fully inserted. No primary or steam generator safety relief valves lifted. The motor driven auxiliary feedwater pumps automatically started on low steam generator level as designed. Decay heat removal is via the steam generators to the main condenser. Offsite power is available and supplying all safeguards busses.

"Unit 2 is unaffected and remains in Mode 5 in a forced outage for 21 RCP [Reactor Coolant Pump] repair.

"During the Fast Bus Transfer [the] 34 Reactor Coolant Pump tripped. The cause is being investigated.

"There was an inadvertent release of CO2 to 31 Main Boiler Feed Pump. The cause was due to the suction relief valve lifting which has subsequently reseated.

"The NRC Sr. Resident Inspector and New York State Public Service Commission have been notified."

The reactor is currently being maintained at normal operating temperature and pressure.

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Thursday, March 29, 2012