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Event Notification Report for May 12, 2003






                    U.S. Nuclear Regulatory Commission

                              Operations Center



                              Event Reports For

                           05/09/2003 - 05/12/2003



                              ** EVENT NUMBERS **



39835  39836  39837  39838  



+------------------------------------------------------------------------------+

|Power Reactor                                    |Event Number:   39835       |

+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+

| FACILITY: RIVER BEND               REGION:  4  |NOTIFICATION DATE: 05/10/2003|

|    UNIT:  [1] [] []                 STATE:  LA |NOTIFICATION TIME: 13:37[EDT]|

|   RXTYPE: [1] GE-6                             |EVENT DATE:        05/10/2003|

+------------------------------------------------+EVENT TIME:        10:28[CDT]|

| NRC NOTIFIED BY:  RICKY MAYEUX                 |LAST UPDATE DATE:  05/10/2003|

|  HQ OPS OFFICER:  HOWIE CROUCH                 +-----------------------------+

+------------------------------------------------+PERSON          ORGANIZATION |

|EMERGENCY CLASS:          NON EMERGENCY         |LINDA SMITH          R4      |

|10 CFR SECTION:                                 |                             |

|NONR                     OTHER UNSPEC REQMNT    |                             |

|                                                |                             |

|                                                |                             |

|                                                |                             |

+-----+----------+-------+--------+-----------------+--------+-----------------+

|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |

+-----+----------+-------+--------+-----------------+--------+-----------------+

|1     N          Y       98       Power Operation  |98       Power Operation  |

|                                                   |                          |

|                                                   |                          |

+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   

+------------------------------------------------------------------------------+

| PLANT MAY HAVE EXCEEDED RATED THERMAL POWER DURING PREVIOUS OPERATING CYCLE  |

|                                                                              |

| The following information was obtained from the licensee via facsimile:      |

|                                                                              |

| "On May 10, 2003, plant personnel determined that River Bend Station [RBS]   |

| may have operated above the licensed thermal power limit of 3039 MWt         |

| [megawatts thermal] during the last operating cycle due to a                 |

| non-conservative error in feedwater flow measurement.  RBS installed a new   |

| feedwater ultrasonic flow meter during the last refueling outage.  Data      |

| analyzed following initial testing of the new flow meter resulted in the     |

| identification of discrepancies between feedwater flow measurements from the |

| new ultrasonic flow meter, the previously installed external ultrasonic flow |

| meter and the venturi nozzle flow meter.  Feedwater flow measurement         |

| directly impacts the calculation of thermal power during plant operation.    |

| The plant normally operates at 100% thermal power.  Thus, any non            |

| conservative error in feedwater measurement results in thermal power greater |

| than 100%.                                                                   |

|                                                                              |

| "Initial review of feedwater flow data indicates that the licensed thermal   |

| power limit may have been exceeded.  Further analysis is ongoing to          |

| determine the magnitude of the condition.  This condition was primarily      |

| caused by error in the flow measurement using the previously installed       |

| external ultrasonic flow meter.  As this device is no longer installed in    |

| the plant, the reported condition has no impact on current plant operation.  |

| This report is being made as required by RBS Operating License [OL]          |

| Condition 2.E as a violation of OL Condition 2.C(1)."                        |

|                                                                              |

| The licensee has notified the NRC Resident Inspector.                        |

+------------------------------------------------------------------------------+



+------------------------------------------------------------------------------+

|Power Reactor                                    |Event Number:   39836       |

+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+

| FACILITY: KEWAUNEE                 REGION:  3  |NOTIFICATION DATE: 05/10/2003|

|    UNIT:  [1] [] []                 STATE:  WI |NOTIFICATION TIME: 17:25[EDT]|

|   RXTYPE: [1] W-2-LP                           |EVENT DATE:        05/10/2003|

+------------------------------------------------+EVENT TIME:        15:06[CDT]|

| NRC NOTIFIED BY:  JAMES BAPTIST                |LAST UPDATE DATE:  05/10/2003|

|  HQ OPS OFFICER:  HOWIE CROUCH                 +-----------------------------+

+------------------------------------------------+PERSON          ORGANIZATION |

|EMERGENCY CLASS:          NON EMERGENCY         |ROGER LANKSBURY      R3      |

|10 CFR SECTION:                                 |                             |

|APRE 50.72(b)(2)(xi)     OFFSITE NOTIFICATION   |                             |

|                                                |                             |

|                                                |                             |

|                                                |                             |

+-----+----------+-------+--------+-----------------+--------+-----------------+

|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |

+-----+----------+-------+--------+-----------------+--------+-----------------+

|1     N          N       0        Hot Shutdown     |0        Hot Shutdown     |

|                                                   |                          |

|                                                   |                          |

+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   

+------------------------------------------------------------------------------+

| OFFSITE NOTIFICATION TO STATE OF WISCONSIN                                   |

|                                                                              |

| The following information was obtained from the licensee via facsimile:      |

|                                                                              |

| "On 5/10/03, while performing a reactor plant startup, the 'B' AFW           |

| [Auxiliary Feed Water] pump Safeguards Alley trench overflowed.  Recent      |

| procedural changes have been made to N-FW-05B which do[es] not allow         |

| throttling of the lube oil coolers discharge valves to prevent flooding. To  |

| address the condition, a sump pump was used to pump water from the trench    |

| directly to the turbine building standpipe because the normal flowpath (     |

| Turbine Building Sump ) capacity had been exceeded. This water is believed   |

| to be free from radiological, chemical, or petroleum products as it is       |

| processed as pure DI [de-ionized] water. This has effectively created a      |

| previously unrecognized and consequently unauthorized discharge flowpath.    |

| This notification is being made due to the expected report to the Wisconsin  |

| DNR [Department of Natural Resources] on the same incident."                 |

|                                                                              |

| To mitigate this condition, the licensee has temporarily changed the revised |

| procedure to allow throttling of lube oil coolers discharge valves (original |

| procedural guidance) until the revised procedure can be re-evaluated.  The   |

| discharge did not exceed any reportable quantities.                          |

|                                                                              |

| The licensee has notified the NRC Resident Inspector.                        |

+------------------------------------------------------------------------------+



+------------------------------------------------------------------------------+

|Power Reactor                                    |Event Number:   39837       |

+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+

| FACILITY: PERRY                    REGION:  3  |NOTIFICATION DATE: 05/10/2003|

|    UNIT:  [1] [] []                 STATE:  OH |NOTIFICATION TIME: 20:54[EDT]|

|   RXTYPE: [1] GE-6                             |EVENT DATE:        05/10/2003|

+------------------------------------------------+EVENT TIME:        15:09[EDT]|

| NRC NOTIFIED BY:  ALAN RABENOLD                |LAST UPDATE DATE:  05/10/2003|

|  HQ OPS OFFICER:  HOWIE CROUCH                 +-----------------------------+

+------------------------------------------------+PERSON          ORGANIZATION |

|EMERGENCY CLASS:          NON EMERGENCY         |ROGER LANKSBURY      R3      |

|10 CFR SECTION:                                 |                             |

|AESF 50.72(b)(3)(iv)(A)  VALID SPECIF SYS ACTUAT|                             |

|                                                |                             |

|                                                |                             |

|                                                |                             |

+-----+----------+-------+--------+-----------------+--------+-----------------+

|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |

+-----+----------+-------+--------+-----------------+--------+-----------------+

|1     M          N       0        Refueling        |0        Refueling        |

|                                                   |                          |

|                                                   |                          |

+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   

+------------------------------------------------------------------------------+

| MANUAL RPS ACTUATION DUE TO FAILED OVERRIDE FEATURE                          |

|                                                                              |

| "At 1509 [CDT], during the performance of the Division One (1) LOOP / LOCA   |

| Test, the instrument air to Control Rods was lost due to a failure of the    |

| supply isolation valve to re-open during the test. It was planned that the   |

| Scram Air Header isolation valve would close during the test but the LOCA    |

| Override feature failed to work and prevented the valve from being           |

| re-opened.  A manual Rx Scram was inserted before Scram Air Header pressure  |

| dropped to the point that it would have caused a Rx Scram.                   |

|                                                                              |

| "The Control Rods were already inserted into the Core and no Rod motion      |

| occurred. The valve was manually re-opened and air was restored to the Scram |

| Air Header.  The Scram was reset at 1546 [hrs.]. The Plant is currently in a |

| Refueling Outage. Troubleshooting will be occurring to determine the failure |

| of the override feature to function:"                                        |

|                                                                              |

| Normal Scram Air Header pressure is 120 psig.  At a pressure of 38 psig, the |

| Scram Air Header valves will start to fail close due to low air pressure and |

| result in a Scram. The licensee initiated the manual Rx Scram when pressure  |

| reached 60 psig decreasing.  The air header depressurized completely until   |

| the air supply valve was manually re-opened after operators were unable to   |

| open the valve from the control room.  During this outage, there was some    |

| work performed on the Scram Air Supply Isolation valve but none that would   |

| have affected the LOCA Override feature.  The Isolation valve override will  |

| be repaired during this refueling outage.                                    |

|                                                                              |

| The licensee has notified the NRC Resident Inspector.                        |

+------------------------------------------------------------------------------+



+------------------------------------------------------------------------------+

|Power Reactor                                    |Event Number:   39838       |

+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+

| FACILITY: SUMMER                   REGION:  2  |NOTIFICATION DATE: 05/12/2003|

|    UNIT:  [1] [] []                 STATE:  SC |NOTIFICATION TIME: 03:28[EDT]|

|   RXTYPE: [1] W-3-LP                           |EVENT DATE:        05/12/2003|

+------------------------------------------------+EVENT TIME:        01:02[EDT]|

| NRC NOTIFIED BY:  EDDIE BYARS                  |LAST UPDATE DATE:  05/12/2003|

|  HQ OPS OFFICER:  JOHN MacKINNON               +-----------------------------+

+------------------------------------------------+PERSON          ORGANIZATION |

|EMERGENCY CLASS:          NON EMERGENCY         |PAUL FREDRICKSON     R2      |

|10 CFR SECTION:                                 |                             |

|ARPS 50.72(b)(2)(iv)(B)  RPS ACTUATION - CRITICA|                             |

|                                                |                             |

|                                                |                             |

|                                                |                             |

+-----+----------+-------+--------+-----------------+--------+-----------------+

|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |

+-----+----------+-------+--------+-----------------+--------+-----------------+

|1     A/R        Y       100      Power Operation  |0        Hot Standby      |

|                                                   |                          |

|                                                   |                          |

+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   

+------------------------------------------------------------------------------+

| AUTOMATIC TURBINE TRIP/REACTOR TRIP DUE TO MAIN GENERATOR OUTPUT BREAKER     |

| OPENING                                                                      |

|                                                                              |

| Main Generator output breaker opened after receiving Main Generator voltage  |

| regulator # 1 (core 1)  & # 2 (core 2) alarms causing an automatic turbine   |

| trip followed by an automatic reactor trip  (first out annunciator was over  |

| temperature differential temperature). All rods fully inserted into the      |

| core. Both motor driven auxiliary feedwater pumps were manually started to   |

| maintain reactor coolant temperature and proper steam generator water        |

| levels.  Steam is being dumped to the main condenser.  Emergency Operating   |

| procedure 1.0 entered and then Emergency Operating procedure 1.1, Reactor    |

| Recovery Procedure was entered.   All emergency core cooling systems and the |

| emergency diesel generators are fully operable if needed.  The licensee      |

| believes that the main generator exciter breaker opened before the main      |

| generator output breaker opened. No work was going on in the area of the     |

| main generator when the output breaker opened.                               |

|                                                                              |

| The NRC Resident Inspector was notified of this event by the licensee.       |

+------------------------------------------------------------------------------+



                    

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