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Event Notification Report for December 17, 2004

U.S. Nuclear Regulatory Commission
Operations Center

Event Reports For
12/16/2004 - 12/17/2004

** EVENT NUMBERS **


41252 41255 41262

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Power Reactor Event Number: 41252
Facility: RIVER BEND
Region: 4 State: LA
Unit: [1] [ ] [ ]
RX Type: [1] GE-6
NRC Notified By: GARY HUSTON
HQ OPS Officer: MIKE RIPLEY
Notification Date: 12/10/2004
Notification Time: 17:34 [ET]
Event Date: 12/10/2004
Event Time: 13:17 [CST]
Last Update Date: 12/16/2004
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL
Person (Organization):
LINDA SMITH (R4)
MICHAEL TSCHILTZ (NRR)
SUSAN FRANT (IRD)

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

Event Text

REACTOR SCRAM DUE TO LOSS OF VITAL INSTRUMENT BUS

"At 1317 [hrs CST] on December 10, 2004, an automatic actuation of the reactor protection system (RPS) occurred resulting in a reactor scram. The apparent cause of the event was loss of a vital instrument bus due to a fault in a nonsafety related vital inverter. This inverter provides power to selected control room instrumentation and controls. This resulted in the loss of feed water level control.

"Reactor level is being maintained by the High Pressure Core Spray System. The feed water system is not available. Reactor pressure is being controlled through the main turbine steam bypass system to the condenser. The condenser is available and being used as the heat sink. The residual heat removal system was operated in suppression pool cooling mode to provide a means of rejecting water from the suppression pool [water input from High Pressure Core Spray System minimum flow line]. The plant is currently stable, and being maintained in hot shutdown. Systems responded as expected based on the initiating event. Reactor Core Isolation Cooling is not being used pending evaluation of a system alarm that is currently being investigated. Investigation of the initiating fault is being pursued in order to recover the vital bus and feed water level control."

It has been preliminarily determined that the loss of instrument power resulted in the Main Feedwater regulating valve failing as-is and the "B" Reactor Recirculation Pump shifting down in speed. The reduction in reactor power with constant feed flow resulted in a high reactor vessel water level, producing a direct reactor scram signal at the High Level 8 setpoint.

The licensee has notified the NRC Resident Inspector.

* * * UPDATE FROM G. HUSTON TO M. RIPLEY AT 2025 EST 12/10/04 * * *

"At 1657 CST [on 12/10/04], reactor level control was restored to the normal Feedwater and Condensate Systems. The High Pressure Core Spray System was restored to the normal standby lineup. Investigation into the cause of the reported RPS actuation continues. Investigation into the Reactor Core Isolation Cooling System alarms has resulted in declaring this system inoperable."

The licensee will notify the NRC Resident Inspector. Notified R4 DO (L. Smith), NRR EO (M. Tschiltz) and IRD Manager (S. Frant)

* * * UPDATE TO W GOTT AT 0016 EST ON 12/12/04 * * *

"The final determination of the cause of the scram was determined to be due to the B recirc pump downshift and subsequent power to flow scram on APRM flux."

The licensee will notify the NRC Resident Inspector.

Notified R4DO (L Smith)

* * * UPDATE TO JOHN MACKINNON FROM HUSTON AT 1332 EST ON 12/16/O4 * * *

"The Reactor Core Cooling System was returned to available status at 0343 on 12/11/2004 and was restored to operable status at 2200 on 12/11/2004."

The licensee notified the NRC Resident Inspector.

Notified R4DO (Kriss Kennedy).

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General Information or Other Event Number: 41255
Rep Org: TEXAS DEPARTMENT OF HEALTH
Licensee: STORK SOUTHWESTERN LABS
Region: 4
City: HOUSTON State: TX
County:
License #: L05269-000
Agreement: Y
Docket:
NRC Notified By: JAMES OGDEN
HQ OPS Officer: MIKE RIPLEY
Notification Date: 12/13/2004
Notification Time: 15:35 [ET]
Event Date: 12/10/2004
Event Time: 16:15 [CST]
Last Update Date: 12/13/2004
Emergency Class: NON EMERGENCY
10 CFR Section:
AGREEMENT STATE
Person (Organization):
GREG PICK (R4)
TRISH HOLAHAN (NMSS)
AARON DANIS (TAS)
FAX TO CNSNS MEX ()

Event Text

AGREEMENT STATE REPORT - STOLEN TROXLER MOISTURE DENSITY GAUGE

On December 10, 2004, (Friday), the Licensee had dispatched operator [deleted], for a job with a Troxler 3440, Serial No. 33733, containing two sealed Special Form sources: 8.0 mCi (nominal) Cs-137, Serial No 750-9391, and 40.0 mCi (nominal) Am-241/Be, Serial No 47-22867. Upon completion of the job the operator was returning to the company office, he decided to stop by the Wal Mart store in Harris County, Texas. Upon returning to his company truck, Ford F150 fleetside, License Plate No. [deleted], he determined that the gauge was missing from the tiedown location. Looking into the bed of the truck he noted that the cable securing the gauge to the truck had been cut and was laying in the bottom of the truck bed near the tailgate, still locked into place. The operator reported the incident to his supervisor and was advised to report the incident to the Harris County Constable's Office - Precinct #4. While he was making the report, Case No 0412101909, the company R.S.O. reported the incident to the Texas Department of State Health Services (DSHS) on-call duty officer. Due to the R.S.O. being at home, he did not have the source Serial Numbers. The source serial numbers were reported to the Agency on Monday afternoon at 1:15 p.m.

Licensee is considering offering a reward and announcing the loss to local media.

Texas Incident No.: I-8191

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General Information or Other Event Number: 41262
Rep Org: NC DIV OF RADIATION PROTECTION
Licensee: ENGINEERING TECHTONICS
Region: 1
City: WINSTON-SALEM State: NC
County:
License #:
Agreement: Y
Docket:
NRC Notified By: LEE COX
HQ OPS Officer: BILL HUFFMAN
Notification Date: 12/14/2004
Notification Time: 23:09 [ET]
Event Date: 12/14/2004
Event Time: 15:00 [EST]
Last Update Date: 12/15/2004
Emergency Class: NON EMERGENCY
10 CFR Section:
AGREEMENT STATE
Person (Organization):
KENNETH JENISON (R1)
MELVYN LEACH (NMSS)

Event Text

AGREEMENT STATE REPORT OF PORTABLE NUCLEAR GAUGE LOST DURING TRUCK CRASH

A representative from the North Carolina Radiation Materials Branch called to report the loss of a Humboldt Portable Nuclear Gauge (Serial #254; Model 5001) due a severe truck crash on or near highway 52 close to Winston-Salem NC. The accident occurred around 15:00 on 12/14/04. The gauge is believe to have a 10 milliCurie Cs-137; 40 milliCurie Am-241,Be source.

A truck carrying the gauge had an accident and rolled multiple times. It is believed that the gauge was ejected and probably in brush or woods in the vicinity of the crash site. A search was conducted until dark and will resume tomorrow (12/15/04) at around 0600.

The licensee for the gauge is a company named Engineering Techtonics licensed by NC. The State of NC has contacted the RSO for the company.

* * * UPDATE FROM L COX TO W GOTT AT 0814 ON 12/15/04 * * *

The gauge was recovered at 0742 EST 12/15/04 and is in the possession of the licensee. The gauge was still in its transport case. The case was still locked, the gauge was still locked, and there was no visible damage to the gauge. Radiation surveys of the area are normal. The licensee plans to ship the gauge to the manufacturer for further inspection.

Notified NMSS (J Hickey) and R1DO (K Jenison).

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