U.S. Nuclear Regulatory Commission Operations Center Event Reports For 10/21/2003 - 10/22/2003 ** EVENT NUMBERS ** | Power Reactor | Event Number: 40263 | Facility: CALLAWAY Region: 4 State: MO Unit: [1] [ ] [ ] RX Type: [1] W-4-LP NRC Notified By: Charles Sarrow HQ OPS Officer: MIKE RIPLEY | Notification Date: 10/21/2003 Notification Time: 05:20 [ET] Event Date: 10/21/2003 Event Time: 01:00 [CDT] Last Update Date: 10/21/2003 | Emergency Class: NON EMERGENCY 10 CFR Section: 50.72(b)(2)(i) - PLANT S/D REQD BY TS | Person (Organization): WILLIAM JONES (R4) | Unit | SCRAM Code | RX CRIT | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode | 1 | N | Y | 100 | Power Operation | 70 | Power Operation | Event Text PLANT SHUTDOWN REQUIRED BY TECHNICAL SPECIFICATIONS "Due to failure of an instrument power inverter (NN11) which supplies vital 120Vac bus NN01, Callaway Plant entered L.C.O. 3.8.7, Electrical Power Systems, Inverters - Operating, Condition A at 0721 on October 20, 2003. The inverter supplying the bus is required to meet the LCO. Since the initiation of the inverter failure, the vital instrument bus has been energized from alternate power supply transformers in accordance with plant design and procedures. It is not an acceptable alternative to meet the LCO OPERABILITY requirement. "Details of the impact on the plant due to this failure are detailed in Corrective Actions Program Report (C.A.R.) 200307636. In summary, the bus voltage was lost momentarily, then restored by operation of the inverter static transfer switch. The failure and subsequent restoration of power to AC Vital Bus caused some control systems responses that were corrected by the control room staff. After the event was stabilized, power remained at 100%. "The LCO Action is to restore the inverter to OPERABLE status within twenty four (24) hours, otherwise be in MODE 3 in 6 hours AND be in Mode 5 in thirty six (36) hours. The twenty four hour period ends at 0721 October 21, 2003. In advance of the action time, a controlled plant shutdown to Mode Three (3) was commenced at 0100 on October 21, 2003 at a rate of ten (10) percent per hour. At the time of this report, maintenance efforts have determined that the problem is internal to the inverter Static Transfer Switch, therefore the reduction of power will continue." No safety system actuations resulted from the control power transfer. The licensee has notified the NRC Resident Inspector. | Power Reactor | Event Number: 40266 | Facility: GRAND GULF Region: 4 State: MS Unit: [1] [ ] [ ] RX Type: [1] GE-6 NRC Notified By: WILLIAM B. ABRAHAM HQ OPS Officer: STEVE SANDIN | Notification Date: 10/21/2003 Notification Time: 12:14 [ET] Event Date: 09/27/2003 Event Time: 01:18 [CDT] Last Update Date: 10/21/2003 | Emergency Class: NON EMERGENCY 10 CFR Section: 50.73(a)(1) - INVALID SPECIF SYSTEM ACTUATION | Person (Organization): WILLIAM JONES (R4) | Unit | SCRAM Code | RX CRIT | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode | 1 | N | Y | 100 | Power Operation | 100 | Power Operation | Event Text INVALID HIGH PRESSURE CORE SPRAY (HPCS) ACTUATION DURING SURVEILLANCE TESTING "This report is being made under 10CFR50.73 (a) (2) (iv) (A). "On September 27, 2003, at 0118 hours Central Time, while operating at 100 percent power, Grand Gulf Nuclear Station experienced an invalid actuation of the High Pressure Core Spray (HPCS) System. The invalid signal was the result of an error made while performing a continuity check during a quarterly surveillance. "The invalid HPCS initiation caused the following systems to actuate: HPCS Pump, Division III Diesel Generator (DG) and Standby Service Water (SSW) 'C' (as designed to support DG operation). "Each train actuation was complete, HPCS started and functioned as designed and all support systems functioned properly. "There was an unexpected HPCS pump suction valve transfer to Suppression Pool. The most probable cause of this valve transfer was minor oscillation in Suppression Pool level." The licensee informed the NRC Resident Inspector. | Power Reactor | Event Number: 40268 | Facility: VOGTLE Region: 2 State: GA Unit: [1] [ ] [ ] RX Type: [1] W-4-LP,[2] W-4-LP NRC Notified By: M. SLIVKA HQ OPS Officer: JOHN MacKINNON | Notification Date: 10/22/2003 Notification Time: 02:56 [ET] Event Date: 10/22/2003 Event Time: 01:03 [EDT] Last Update Date: 10/22/2003 | Emergency Class: NON EMERGENCY 10 CFR Section: 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION | Person (Organization): CHARLES R. OGLE (R2) | Unit | SCRAM Code | RX CRIT | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode | 1 | N | Y | 2 | Startup | 2 | Startup | Event Text HIGH PRESSURE HOSE CONNECTION FAILED RESULTING IN A TRAIN "A" MANUAL STEAM LINE ISOLATION "Manually initiated a steam line isolation signal upon report of a failed connection on a high pressure hose being used to vent a main steam isolation valve bonnet cavity (to open pressure locked valves). The manual isolation resulted in closure of the four open main steam isolation valves (Train "A"). The isolation was conducted as a preventative measure for personnel protection (three people were in the South Main Steam Valve Room when the fitting failed). No personnel were injured. Plant conditions remained stable." The NRC Resident Inspector was notified of this event by the licensee. | |