Event Notification Report for September 5, 2001
U.S. Nuclear Regulatory Commission
Operations Center
Event Reports For
09/04/2001 - 09/05/2001
** EVENT NUMBERS **
38263 38264 38265
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|Power Reactor |Event Number: 38263 |
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| FACILITY: WATTS BAR REGION: 2 |NOTIFICATION DATE: 09/04/2001|
| UNIT: [1] [] [] STATE: TN |NOTIFICATION TIME: 16:54[EDT]|
| RXTYPE: [1] W-4-LP,[2] W-4-LP |EVENT DATE: 09/04/2001|
+------------------------------------------------+EVENT TIME: 13:04[EDT]|
| NRC NOTIFIED BY: RODEN |LAST UPDATE DATE: 09/04/2001|
| HQ OPS OFFICER: CHAUNCEY GOULD +-----------------------------+
+------------------------------------------------+PERSON ORGANIZATION |
|EMERGENCY CLASS: NON EMERGENCY |JOHN MONNINGER R2 |
|10 CFR SECTION: | |
|ARPS 50.72(b)(2)(iv)(B) RPS ACTUATION - CRITICA| |
|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/R Y 100 Power Operation |0 Hot Standby |
| | |
| | |
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EVENT TEXT
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| REACTOR MANUALLY TRIPPED FROM 100% POWER DUE TO STEAM GENERATOR LEVEL |
| APPROACHING THE LO-LO LEVEL SETPOINT |
| |
| While operating at 100% power, the Watts Bar Unit 1 reactor was manually |
| tripped at approximately 1304 EDT on September 4, 2001 due to steam |
| generator (SG) level approaching the Lo-Lo level setpoint. Just prior to |
| the manual trip of the reactor, an abnormal voltage alarm was received on |
| 125V Vital Battery Board 1-1. The immediate cause of the trip is considered |
| to be the loss of the 1-1 Vital AC Inverter which caused a feedwater |
| regulating valve to close. Subsequently, the maintenance power supply was |
| used to restore power to the 1-1 vital AC bus. |
| |
| All control rods inserted properly in response to the reactor trip. The |
| Auxiliary Feedwater (AFW) System actuated as expected. However, subsequent |
| to the initial actuation signal, additional operator action was required |
| to[manually] start 1B motor driven pump. After the 1B pump was |
| successfully started, the motor driven AFW pump 1A was secured based on |
| instrument indications available to the operating staff. After power was |
| restored to the vital AC bus, the 1A pump was subsequently started and |
| performed properly. Inspections are currently underway to determine the |
| exact cause of the loss of the 1-1 Vital Inverter and basis for the 1B pump |
| failing to [auto] start. |
| |
| No ECCS injection occurred, but the steam generator atmospheric relief |
| valves lifted and fully reseated. |
| |
| The manual actuation of the Reactor Protection System (RPS) is being |
| reported as a four hour report under 10 CFR 50.72 (b)(2)(iv). The actuation |
| of the Auxiliary Feedwater System (an engineered safety feature) is being |
| reported as an eight hour report under 10 CFR 50.72 (b)(3)(iv). |
| |
| The plant is stable in mode 3. |
| |
| The NRC Resident Inspector was notified. |
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|Power Reactor |Event Number: 38264 |
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| FACILITY: CALVERT CLIFFS REGION: 1 |NOTIFICATION DATE: 09/04/2001|
| UNIT: [1] [2] [] STATE: MD |NOTIFICATION TIME: 17:00[EDT]|
| RXTYPE: [1] CE,[2] CE |EVENT DATE: 09/04/2001|
+------------------------------------------------+EVENT TIME: 15:00[EDT]|
| NRC NOTIFIED BY: LAVATE |LAST UPDATE DATE: 09/04/2001|
| HQ OPS OFFICER: CHAUNCEY GOULD +-----------------------------+
+------------------------------------------------+PERSON ORGANIZATION |
|EMERGENCY CLASS: NON EMERGENCY |HAROLD GRAY R1 |
|10 CFR SECTION: | |
|ACOM 50.72(b)(3)(xiii) LOSS COMM/ASMT/RESPONSE| |
| | |
| | |
| | |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1 N Y 100 Power Operation |100 Power Operation |
|2 N Y 100 Power Operation |100 Power Operation |
| | |
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EVENT TEXT
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| FAILURE OF 17 OUT OF THE 49 EMERGENCY NOTIFICATION SYSTEM SIRENS FOR CALVERT |
| COUNTY |
| |
| The licensee reported that 17 out of 49 sirens in Calvert County failed to |
| respond to the scheduled county test.. However, all sirens did respond to |
| a mobile siren test kit which is used locally at the siren. Calvert County |
| Emergency Management was notified to perform route alerting in the affected |
| areas in the event of an emergency. The cause is believed to be a |
| transmission problem. |
| |
| The NRC Resident Inspector will be notified. The county has been notified. |
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|Fuel Cycle Facility |Event Number: 38265 |
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| FACILITY: PADUCAH GASEOUS DIFFUSION PLANT |NOTIFICATION DATE: 09/04/2001|
| RXTYPE: URANIUM ENRICHMENT FACILITY |NOTIFICATION TIME: 18:09[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER |EVENT DATE: 09/04/2001|
| 6903 ROCKLEDGE DRIVE |EVENT TIME: 14:00[CDT]|
| BETHESDA, MD 20817 (301)564-3200 |LAST UPDATE DATE: 09/04/2001|
| CITY: PADUCAH REGION: 3 +-----------------------------+
| COUNTY: McCRACKEN STATE: KY |PERSON ORGANIZATION |
|LICENSE#: GDP-1 AGREEMENT: Y |MARK RING R3 |
| DOCKET: 0707001 |M. WAYNE HODGES NMSS |
+------------------------------------------------+ |
| NRC NOTIFIED BY: UNDERWOOD | |
| HQ OPS OFFICER: CHAUNCEY GOULD | |
+------------------------------------------------+ |
|EMERGENCY CLASS: NON EMERGENCY | |
|10 CFR SECTION: | |
|NBNL RESPONSE-BULLETIN | |
| | |
| | |
| | |
| | |
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EVENT TEXT
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| 24-HOUR 91-01 BULLETIN RESPONSE |
| |
| At 1400, on 9/4/01, the Plant Shift Superintendent (PSS) was notified of an |
| NCSA violation that had occurred at the C-355 air plant. Immediately after |
| switching drying units at the air plant, a high-high moisture alarm was |
| received. The alarm indicated air moisture content greater than 1300 ppm |
| water, violating NCSA GEN-10-01. NCSA GEN-010 credits the dry air system |
| for producing dry air with moisture content of less than 1300 ppm. The |
| purpose of this requirement is to prevent exposure of fissile uranium |
| deposits to a moderating environment. No equipment containing fissile |
| material was exposed to high moisture content plant air at the time of the |
| alarm or following receipt of the alarm. |
| |
| Since one leg of double contingency was lost, this is being reported to the |
| NRC as a 24-hr. event report. |
| |
| SAFETY SIGNIFICANCE OF EVENTS: |
| There was no purging of equipment containing fissile material in progress at |
| the time of the moisture excursion. Although a parameter was exceeded, the |
| proper response to the alarm was taken prior to resuming buffering of |
| purging equipment containing fissile material. |
| |
| POTENTIAL CRITICALITY PATHWAYS INVOLVED(BRIEF SCENARIO(S) OF HOW CRITICALITY |
| COULD OCCUR: |
| In order for a criticality to be possible. Operations personnel would have |
| had to fail to respond to the alarm. In addition, a fissile deposit |
| containing greater than a critical mass and absorbing greater than 10 kg of |
| water would have had to be present. |
| |
| CONTROLLED PARAMETERS (MASS, MODERATION. GEOMETRY, CONCENTRATION. ETC: |
| Double contingency for this scenario is established by implementing two |
| controls on moderation. |
| |
| ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL (INCLUDE PROCESS |
| LIMIT AND % WORST CASE CRITICAL MASS): |
| n/a |
| |
| NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION |
| OF THE FAILURES OR DEFICIENCIES: |
| Double contingency for this scenario is established by implementing two |
| controls on moderation. |
| |
| The first leg of double contingency Is based on receiving a high-high |
| moisture alarm indicating a moisture content greater than 1300 ppm water and |
| ceasing buffering and purging operations in response to the alarm. This |
| control was not violated. |
| |
| The second leg of double contingency is based on the dry air system |
| producing plant air with a moisture content less than 1300 ppm water. Since |
| the moisture content was confirmed to be greater than 1300 ppm, this process |
| condition was exceeded and double contingency was not maintained. |
| |
| Since double contingency is based on two controls on moderation, double |
| contingency was not maintained. |
| |
| CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED: |
| No corrective actions implemented. Proper procedure response was performed. |
| |
| The NRC Resident Inspector was notified. |
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Page Last Reviewed/Updated Wednesday, March 24, 2021
Page Last Reviewed/Updated Wednesday, March 24, 2021