Event Notification Report for June 21, 1999
U.S. Nuclear Regulatory Commission Operations Center Event Reports For 06/18/1999 - 06/21/1999 ** EVENT NUMBERS ** 35790 35801 35832 35834 35841 35842 35843 35844 35845 35846 35847 35848 +------------------------------------------------------------------------------+ |Fuel Cycle Facility |Event Number: 35790 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | FACILITY: PADUCAH GASEOUS DIFFUSION PLANT |NOTIFICATION DATE: 06/03/1999| | RXTYPE: URANIUM ENRICHMENT FACILITY |NOTIFICATION TIME: 14:44[EDT]| | COMMENTS: 2 DEMOCRACY CENTER |EVENT DATE: 06/02/1999| | 6903 ROCKLEDGE DRIVE |EVENT TIME: 16:30[CDT]| | BETHESDA, MD 20817 (301)564-3200 |LAST UPDATE DATE: 06/18/1999| | CITY: PADUCAH REGION: 3 +-----------------------------+ | COUNTY: McCRACKEN STATE: KY |PERSON ORGANIZATION | |LICENSE#: GDP-1 AGREEMENT: Y |DAVID HILLS R3 | | DOCKET: 0707001 |DON COOL NMSS | +------------------------------------------------+ | | NRC NOTIFIED BY: THOMAS WHITE | | | HQ OPS OFFICER: FANGIE JONES | | +------------------------------------------------+ | |EMERGENCY CLASS: N/A | | |10 CFR SECTION: | | |OCBA 76.120(c)(2)(i) ACCID MT EQUIP FAILS | | | | | | | | | | | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | THREE SPRINKLER SYSTEMS DECLARED INOPERABLE DUE TO CORRODED HEADS (24-hour | | report) | | | | The following text is a portion of a facsimile received from Paducah: | | | | "On 06/02/99 at 1630 CDT, the Plant Shift Superintendent (PSS) was notified | | that numerous sprinkler heads were corroded, affecting 16 sprinkler systems | | in C-337 and one system in C-333, such that the ability of the sprinklers to | | flow sufficient water was called into question. Subsequently, these | | sprinkler systems were declared inoperable, and TSR-required actions | | establishing roving fire patrols were initiated. This deficiency was | | detected during scheduled system inspections conducted by Fire Protection | | personnel. Currently, functionality of the sprinkler heads has not been | | fully evaluated by Fire Protection personnel, and the remaining cascade | | buildings are currently being inspected, and if necessary, this report will | | be updated to identify any additional areas. | | | | "It has been determined that this event is reportable under | | 10CFR76.120(c)(2) as an event in which equipment is disabled or fails to | | function as designed." | | | | The NRC resident inspector has been notified of this event. | | | | ******************** UPDATE RECEIVED AT 1022 EDT ON 06/04/99 FROM CAGE TO | | TROCINE ******************* | | | | The following text is a portion of a facsimile received from Paducah: | | | | "Two sprinkle heads on system D-1 in C-337 and two sprinkler heads on system | | 27 in C-335 were identified to also be corroded. These were identified to | | the PSS on 06/03/99 at 1600 CDT and 1601 CDT, respectively, and determined | | to require an update to this report by the PSS. | | | | "It has been determined that this event is reportable under | | 10CFR76.120(c)(2) as an event in which equipment is disabled or fails to | | function as designed." | | | | Paducah personnel notified the NRC resident inspector of this update. The | | NRC operations officer notified the R3DO (Hills) and NMSS EO (Combs). | | | | *********** UPDATE RECEIVED AT 2152 EDT ON 06/17/99 FROM WALKER TO POERTNER | | *********** | | | | The following text is a portion of a facsimile received from Paducah: | | | | "Three sprinkler heads on system C-15 and five sprinkler heads on system B-8 | | in C-333 were identified to also be corroded. The PSS was notified of this | | condition at 1300 CDT on 06/17/99 and determined that an update to this | | report was required." | | | | "It has been determined that this event is reportable under | | 10CFR76.120(c)(2) as an event in which equipment is disabled or fails to | | function as designed." | | | | Paducah personnel notified the NRC resident inspector of this update. The | | NRC operations officer notified the R3DO (Madera). | | | | * * * UPDATE AT 1440 ON 06/18/99 FROM UNDERWOOD TAKEN BY STRANSKY * * * | | | | "Two sprinkler heads on system C-15 and one sprinkler head on system B-8 in | | C-333 were identified to have corrosion. The PSS was notified of this | | condition at 1350 CDT on 06/18/99. The area of the fire patrol for system | | C-15 was expanded to include the two heads identified as corroded. The one | | head on system B-8 was in the area already being patrolled. The PSS | | determined that an update to this report was required." | | | | The NRC resident inspector has been informed of this update. The NRC | | operations officer notified R3DO (Madera). | +------------------------------------------------------------------------------+ !!!!!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED !!!!!!! +------------------------------------------------------------------------------+ |Power Reactor |Event Number: 35801 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | FACILITY: QUAD CITIES REGION: 3 |NOTIFICATION DATE: 06/06/1999| | UNIT: [1] [] [] STATE: IL |NOTIFICATION TIME: 18:07[EDT]| | RXTYPE: [1] GE-3,[2] GE-3 |EVENT DATE: 06/06/1999| +------------------------------------------------+EVENT TIME: 14:40[CDT]| | NRC NOTIFIED BY: MIKE MacLENNON |LAST UPDATE DATE: 06/18/1999| | HQ OPS OFFICER: FANGIE JONES +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |DAVID HILLS R3 | |10 CFR SECTION: | | |AESF 50.72(b)(2)(ii) ESF ACTUATION | | | | | | | | | | | +-----+----------+-------+--------+-----------------+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ |1 N Y 100 Power Operation |55 Power Operation | | | | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | LIGHTNING STRIKE CAUSED SOME MINOR ALARMS AND PARTIAL GROUP ONE ISOLATIONS | | | | "On 06/06/99 at approximately 1440, a lightning strike caused valves | | 1-0220-44 and 1-0220-45, Reactor Recirculation sample valves, to close on an | | invalid signal. These valves close automatically on a Group 1 isolation, | | and therefore this is considered to be an ESF actuation. | | | | "The power change indicated above was also a result of the lightning strike. | | An emergency load reduction was made in response to a partial loss of | | feedwater heaters. Reactor recirculation flow was manually reduced and | | control rods were inserted to reduce the flow control line below 100%. | | Miscellaneous other minor alarms were received on both units due to the | | lightning strike. | | | | "The above sample valves have been reopened, and a load increase to full | | power has been initiated at 1635." | | | | The licensee notified the NRC Resident Inspector. | | | | * * * UPDATE AT 1115 ON 06/18/99 BY VENCI RECEIVED BY WEAVER * * * | | | | On 06/06/99, an ENS notification was made in accordance with | | 10CFR50.72(b)(2)(ii) as an ESF actuation. A lightning strike caused the | | reactor recirculation sample valves, 1-0220-44 and 1-0220-45 to close on an | | invalid signal. These valves close on a Group 1 isolation signal. | | | | The subsequent evaluation determined that there were no conditions present | | to actuate these valves from a Group 1 signal and the PCI logic circuitry | | was not actuated. Apparently, the lightning strike caused a minor power | | disturbance of the instrument bus that resulted in the solenoid valves, | | associated with the reactor recirculation sample valves, to lose power. | | This caused closure of the 1-0220-44 and 1-0220-45 valves. | | | | Quad Cities experienced an invalid signal with no actuation of ESF logic. | | Therefore, this event is being retracted. | | | | The licensee informed the NRC Resident Inspector. The NRC Operations | | Officer notified the R3DO (Madera). | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ |Power Reactor |Event Number: 35832 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | FACILITY: INDIAN POINT REGION: 1 |NOTIFICATION DATE: 06/16/1999| | UNIT: [] [3] [] STATE: NY |NOTIFICATION TIME: 18:57[EDT]| | RXTYPE: [2] W-4-LP,[3] W-4-LP |EVENT DATE: 06/16/1999| +------------------------------------------------+EVENT TIME: 18:15[EDT]| | NRC NOTIFIED BY: CHARLIE KOCSIS |LAST UPDATE DATE: 06/18/1999| | HQ OPS OFFICER: WILLIAM POERTNER +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |JIMI YEROKUN R1 | |10 CFR SECTION: | | |AOUT 50.72(b)(1)(ii)(B) OUTSIDE DESIGN BASIS | | | | | | | | | | | +-----+----------+-------+--------+-----------------+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ | | | |3 N Y 100 Power Operation |100 Power Operation | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | HIGH HEAD SAFETY INJECTION EXTERNAL LEAKAGE. | | | | On 06/16/99, operators identified packing leakage from a drain valve in the | | high head safety injection system (valve SI-105). When the leakage was | | added to the existing system leakage, the control room ventilation system | | exceeded its system design basis calculation assumption for external | | recirculation system leakage (0.68 gph). The control room ventilation | | system continues to remain operable per an existing operability | | determination (OD 98-16). Leakage was subsequently reduced, such that total | | system leakage was within design base limits. | | | | The licensee plans to notify the NRC resident inspector. | | | | * * * UPDATE AT 1318 ON 06/18/99 FROM DECLEMENTE TAKEN BY STRANSKY * * * | | | | "On 06/16/99, while the plant was in operation, operators identified active | | packing leakage from a drain valve in the high head safety injection system | | (valve SI-105). When the leakage is added to the existing system leakage, | | the control room ventilation system exceeded its system design basis | | calculation assumption for external recirculation system leakage (0.68 gph). | | The control room ventilation system continues to remain operable per an | | existing operability determination (OD 98-16). Following discovery of the | | active packing leak, adjustments were made that reduced leakage. However, | | the subsequent calculated leak rate shows the leak rate still remained | | greater than 0.68 gph, specifically 0.683 gph. | | | | "During another test procedure, PT-Q116, packing leakage from valve | | SI-MOV-851B, 32 safety injection pump discharge isolation valve was found on | | 06/18/99. Total leak rate of systems outside containment likely to contain | | radioactive material is 0.689 gph." | | | | The licensee will inform the NRC Resident Inspector. The NRC Operations | | Officer notified R1DO (Yerokun). | +------------------------------------------------------------------------------+ !!!!!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED !!!!!!! +------------------------------------------------------------------------------+ |Power Reactor |Event Number: 35834 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | FACILITY: HATCH REGION: 2 |NOTIFICATION DATE: 06/16/1999| | UNIT: [1] [2] [] STATE: GA |NOTIFICATION TIME: 20:57[EDT]| | RXTYPE: [1] GE-4,[2] GE-4 |EVENT DATE: 06/16/1999| +------------------------------------------------+EVENT TIME: 20:00[EDT]| | NRC NOTIFIED BY: BARRY COLEMAN |LAST UPDATE DATE: 06/18/1999| | HQ OPS OFFICER: WILLIAM POERTNER +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |CAUDLE JULIAN R2 | |10 CFR SECTION: | | |DDDD 73.71 UNSPECIFIED PARAGRAPH | | | | | | | | | | | +-----+----------+-------+--------+-----------------+--------+-----------------+ |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 N 0 Hot Shutdown |0 Hot Shutdown | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | PHYSICAL SECURITY REPORT | | | | Plant access granted inappropriately. Immediate compensatory measures taken | | upon discovery. The licensee notified the NRC resident inspector. | | | | Refer to HOO Log for additional details. | | | | * * * RETRACTION AT 1312 ON 06/18/99 FROM BARNES TAKEN BY STRANSKY * * * | | | | The licensee has determined that this event is not reportable, and this | | notification is being retracted. The licensee will inform the NRC Resident | | Inspector. The NRC Operations Officer notified R2DO (Julian). | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ |Power Reactor |Event Number: 35841 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | FACILITY: PALISADES REGION: 3 |NOTIFICATION DATE: 06/18/1999| | UNIT: [1] [] [] STATE: MI |NOTIFICATION TIME: 01:41[EDT]| | RXTYPE: [1] CE |EVENT DATE: 06/17/1999| +------------------------------------------------+EVENT TIME: 22:40[EDT]| | NRC NOTIFIED BY: BRUCE HOWARD |LAST UPDATE DATE: 06/18/1999| | HQ OPS OFFICER: DOUG WEAVER +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |JOHN MADERA R3 | |10 CFR SECTION: | | |NINF INFORMATION ONLY | | | | | | | | | | | +-----+----------+-------+--------+-----------------+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ |1 N Y 100 Power Operation |100 Power Operation | | | | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | INFORMATION CALL - A FIRE ON OWNER CONTROLLED PROPERTY | | | | A fire of undetermined origin was discovered by a janitor at 2240 on | | 06/17/99 in a temporary office trailer, north of the Palisades Training | | Building. The trailer complex is located one-half mile from the operating | | plant. There was no impact to the Training Building or the plant's | | operation, and the plant remained at full power. | | | | The control room was notified after discovery of the blaze. The control | | room dispatched the plant's fire brigade and Covert Fire and Ambulance | | department to the scene. The plant fire brigade began immediate setup of | | hoses and began initial fire fighting until the Covert Fire department | | arrived, some 15 minutes later. | | | | The cause of the fire has not been determined. An investigation will be | | initiated. There were no injuries and no one was in the trailer office at | | the time. | | | | A safety inspection of all plant offices and trailers for potential fire | | hazards will be conducted on 06/18/99. | | | | The licensee notified the NRC Resident Inspector. | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ |Power Reactor |Event Number: 35842 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | FACILITY: LASALLE REGION: 3 |NOTIFICATION DATE: 06/18/1999| | UNIT: [] [2] [] STATE: IL |NOTIFICATION TIME: 05:48[EDT]| | RXTYPE: [1] GE-5,[2] GE-5 |EVENT DATE: 06/18/1999| +------------------------------------------------+EVENT TIME: 02:50[CDT]| | NRC NOTIFIED BY: JIM SPIELER |LAST UPDATE DATE: 06/18/1999| | HQ OPS OFFICER: DOUG WEAVER +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |JOHN MADERA R3 | |10 CFR SECTION: | | |AESF 50.72(b)(2)(ii) ESF ACTUATION | | | | | | | | | | | +-----+----------+-------+--------+-----------------+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ | | | |2 N Y 100 Power Operation |100 Power Operation | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | ESF ACTUATION - VACUUM BREAKER | | | | At 0250 CDT, #2PC001D, the 2D Primary Containment Vacuum Breaker went from | | the (normal) closed position to an indicated dual position. Locally, it was | | determined that the valve was just cracked open. The valve is designed to | | open when suppression chamber pressure is approximately 0.5 psig greater | | than drywell pressure. When the vacuum breaker opened the aforementioned | | differential pressure was approximately 0.2 psid. The vacuum breaker was | | closed by an equipment attendant and then cycled per LOS-PC-M2 "Unit 2 | | Drywell-Suppression Pool Vacuum Breaker Operability Test for Condition 1, 2 | | and 3" to verify proper operation. The valve cycled satisfactorily. | | | | The licensee notified the NRC resident inspector. | | | | NOTE: THIS EVENT IS SIMILAR TO EVENT #35840. | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ |General Information or Other |Event Number: 35843 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | REP ORG: NC DIVISION OF RADIATION PROTECTION |NOTIFICATION DATE: 06/18/1999| |LICENSEE: BARNHILL CONSTRUCTION |NOTIFICATION TIME: 08:45[EDT]| | CITY: ROBERSON REGION: 2 |EVENT DATE: 06/14/1999| | COUNTY: MARTIN STATE: NC |EVENT TIME: 12:00[EDT]| |LICENSE#: NC-092-0958-1 AGREEMENT: Y |LAST UPDATE DATE: 06/18/1999| | DOCKET: |+----------------------------+ | |PERSON ORGANIZATION | | |CAUDLE JULIAN R2 | | |FRED COMBS NMSS | +------------------------------------------------+ | | NRC NOTIFIED BY: MR. JEFFRIES | | | HQ OPS OFFICER: DOUG WEAVER | | +------------------------------------------------+ | |EMERGENCY CLASS: N/A | | |10 CFR SECTION: | | |NAGR AGREEMENT STATE | | |NDAM DAMAGED GAUGE/DEVICE | | | | | | | | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | DAMAGED MOISTURE DENSITY GAUGE | | | | A TROXLER MOISTURE DENSITY GAUGE WAS DAMAGED BY A MOTORIST AT A CONSTRUCTION | | WORKSITE ALONG HIGHWAY 64 IN MARTIN COUNTY, NC. THE GAUGE WAS SEVERELY | | DAMAGED AS WAS THE SOURCE TUBE, BUT NO CONTAMINATION WAS SPREAD BY THIS | | INCIDENT. THE GAUGE HAS BEEN RETURNED TO TROXLER. THE GAUGE IS A MODEL | | 4640B CONTAINING A 8 mCi Cs-137 SOURCE. | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ |General Information or Other |Event Number: 35844 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | REP ORG: ROSEMOUNT NUCLEAR INSTRUMENTS, INC. |NOTIFICATION DATE: 06/18/1999| |LICENSEE: ROSEMOUNT NUCLEAR INSTRUMENTS, INC |NOTIFICATION TIME: 12:28[EDT]| | CITY: EDEN PRAIRIE REGION: 3 |EVENT DATE: 06/18/1999| | COUNTY: STATE: MN |EVENT TIME: 10:00[CDT]| |LICENSE#: AGREEMENT: N |LAST UPDATE DATE: 06/18/1999| | DOCKET: |+----------------------------+ | |PERSON ORGANIZATION | | |VERN HODGE (via fax) NRR | | | | +------------------------------------------------+ | | NRC NOTIFIED BY: GERRY HANSON | | | HQ OPS OFFICER: BOB STRANSKY | | +------------------------------------------------+ | |EMERGENCY CLASS: N/A | | |10 CFR SECTION: | | |CCCC 21.21 UNSPECIFIED PARAGRAPH | | | | | | | | | | | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | 10 CFR PART 21 REPORT REGARDING POTENTIAL NEED FOR CAPACITOR REPLACEMENT IN | | SPECIFIC TRIP/CALIBRATION SYSTEMS | | | | The following is text of a letter submitted to the NRC Operations Center via | | facsimile: | | | | "The purpose of this letter is to inform you that a specific capacitor C25 | | used in Rosemount Trip/Calibration Systems may require replacement. This | | affects all Rosemount Model 510DU Trip Units (obsolete since 1987) and | | certain Rosemount Model 710DU Trip Units. | | | | "Prior to 1987, there were 10 confirmed random failures of C25 capacitors | | used in slave and master trip unit circuit boards. In 1987, a number of | | tests were run on sample capacitors in an attempt to duplicate the failure | | modes. It was found that unless the capacitors were exposed to temperatures | | and voltages in excess of normal operating conditions, no failures were | | induced. However, introduction of a contaminant such as moisture could | | possibly cause this type of failure. As a precautionary measure, a | | component change was instituted on the C25 capacitor beginning with | | manufacturer date code 8630. This change featured an enhanced moisture | | seal. No confirmed failures of the post 8630 date code C25 capacitor have | | been identified. However, Rosemount Nuclear Instruments. Inc is sending | | this letter to affected utilities to remind users that the model 710 and 510 | | trip units with pre-8630 date code C25 capacitors could be susceptible to | | this condition. Failure of the C25 capacitor can cause a low resistance | | condition between the power supply input and chassis ground. This low | | resistance can allow over-current conditions to cause failure of the | | affected unit. | | | | "A letter [enclosed in facsimile] was issued by Rosemount Nuclear | | Instruments Inc to the Scram Frequency Reduction Committee of the BWR | | Owners' Group in response to a BWROG request for information [enclosed in | | facsimile], documenting the change which had been made in 1987. Since that | | time, there have been five additional confirmed C25 failures and fourteen | | additional failures possibly related to the C25 capacitor. Again, all of | | these failures occurred in units with C25 capacitors that had date codes of | | pre-8630. The total number of model 510 and 710 trip units shipped with the | | pre-8630 date code capacitors was 18,164. We believe that recent failures | | may warrant further examination of your 510DU/710DU systems to determine | | whether replacement of the pre-8630 date code capacitors is warranted." | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ |Power Reactor |Event Number: 35845 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | FACILITY: PALO VERDE REGION: 4 |NOTIFICATION DATE: 06/19/1999| | UNIT: [] [2] [] STATE: AZ |NOTIFICATION TIME: 04:16[EDT]| | RXTYPE: [1] CE,[2] CE,[3] CE |EVENT DATE: 06/18/1999| +------------------------------------------------+EVENT TIME: 22:29[MST]| | NRC NOTIFIED BY: DAN MARKS |LAST UPDATE DATE: 06/19/1999| | HQ OPS OFFICER: DICK JOLLIFFE +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |JOHN PELLET R4 | |10 CFR SECTION: | | |ARPS 50.72(b)(2)(ii) RPS ACTUATION | | | | | | | | | | | +-----+----------+-------+--------+-----------------+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ | | | |2 A/R Y 100 Power Operation |0 Hot Standby | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | - Auto reactor trip from 100% power due to low DNBR trips due to a failed | | control element assembly calculator - | | | | On 06/18/99, at approximately 2229 MST, Palo Verde Unit 2 experienced a | | reactor trip (RPS actuation) from 100% rated thermal power due to low | | departure from nucleate boiling ratio (DNBR) trips on all four channels of | | the core protection calculators (CPCs). Unit 2 was at normal temperature | | and pressure prior to the trip. | | | | Prior to the reactor trip, at approximately 2204 MST, a CPC channel 'C' | | sensor fail alarm and control element assembly (CEA) withdrawal prohibit | | (CWP) alarm were received and cleared about one second later. While | | investigating the alarms, at 2229 MST, all four CPC channel sensor fail | | alarms and the CWP alarm were received. The reactor automatically tripped | | six seconds later. A CEA calculator (CEAC) fail alarm was received on CEAC | | #2. The apparent cause is presently suspected to be the failure of CEAC #2. | | An investigation has commenced to determine the root cause of the reactor | | trip. | | | | All control rods fully inserted into the core. Four of eight steam bypass | | control valves quick opened, per design, directing steam flow to the main | | condenser. No main steam or primary relief valves lifted and none were | | required. There was no loss of heat removal capability or loss of safety | | functions associated with this event. Electrical buses transferred to | | offsite power, as designed. The Shift Manager determined that this event | | was an uncomplicated reactor trip. No significant LCOs have been entered as | | a result of this event. No major equipment was inoperable prior to the | | event nor contributed to the event, other than the CPCs discussed above. | | | | Unit 2 is stable in Mode 3 (hot standby) at normal operating temperature and | | pressure. No ESF actuations occurred and none were required. The event did | | not result in any challenges to the fission product barrier or result in any | | releases of radioactive materials. There were no adverse safety | | consequences or implications as a result of this event. The event did not | | adversely affect the safe operation of the plant or health and safety of the | | public. | | | | The licensee notified the NRC Resident Inspector. | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ |Power Reactor |Event Number: 35846 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | FACILITY: MILLSTONE REGION: 1 |NOTIFICATION DATE: 06/19/1999| | UNIT: [] [] [3] STATE: CT |NOTIFICATION TIME: 10:34[EDT]| | RXTYPE: [1] GE-3,[2] CE,[3] W-4-LP |EVENT DATE: 06/19/1999| +------------------------------------------------+EVENT TIME: 10:01[EDT]| | NRC NOTIFIED BY: RAY MARTIN |LAST UPDATE DATE: 06/19/1999| | HQ OPS OFFICER: DICK JOLLIFFE +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |JIMI YEROKUN R1 | |10 CFR SECTION: | | |AESF 50.72(b)(2)(ii) ESF ACTUATION | | | | | | | | | | | +-----+----------+-------+--------+-----------------+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ | | | | | | |3 N N 0 Cold Shutdown |0 Cold Shutdown | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | -AFW PUMP STARTED DUE TO LOW S/G LEVEL SIGNALS WHILE VENTING A S/G LEVEL | | TRANSMITTER- | | | | WITH UNIT 3 IN MODE 5 (COLD SHUTDOWN) IN A REFUELING OUTAGE AND THE #2A | | VITAL INSTRUMENT AC BUS INOPERABLE, PLANT TECHNICIANS WERE VENTING AN 'A' | | STEAM GENERATOR (S/G) LEVEL TRANSMITTER. THE 'A' AUXILIARY FEEDWATER (AFW) | | PUMP STARTED DUE TO A LOW S/G LEVEL ACTUATION SIGNAL ALONG WITH A LOW S/G | | LEVEL SIGNAL DUE TO THE #2A VITAL INSTRUMENT AC BUS BEING INOPERABLE (2 OUT | | OF 4 LOGIC ACTUATION SIGNAL). PLANT OPERATORS STOPPED THE 'A' AFW PUMP AND | | RESET IT TO NORMAL WITHIN ONE MINUTE. | | | | THE LICENSEE NOTIFIED STATE AND LOCAL OFFICIALS AND THE NRC RESIDENT | | INSPECTOR. | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ |Power Reactor |Event Number: 35847 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | FACILITY: OCONEE REGION: 2 |NOTIFICATION DATE: 06/19/1999| | UNIT: [] [2] [] STATE: SC |NOTIFICATION TIME: 11:58[EDT]| | RXTYPE: [1] B&W-L-LP,[2] B&W-L-LP,[3] B&W-L-L|EVENT DATE: 06/19/1999| +------------------------------------------------+EVENT TIME: 10:15[EDT]| | NRC NOTIFIED BY: PRESTON GILLESPIE |LAST UPDATE DATE: 06/19/1999| | HQ OPS OFFICER: BOB STRANSKY +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |CAUDLE JULIAN R2 | |10 CFR SECTION: | | |ARPS 50.72(b)(2)(ii) RPS ACTUATION | | | | | | | | | | | +-----+----------+-------+--------+-----------------+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ | | | |2 A/R Y 66 Power Operation |0 Hot Standby | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | AUTOMATIC REACTOR TRIP DUE TO MAIN TURBINE TRIP | | | | The unit experienced an automatic turbine trip/reactor trip due to an | | indicated high moisture separator level. Following the trip, all control | | rods inserted and all systems functioned as required. The reactor is | | currently stable in Mode 3, with steam generator levels being maintained by | | the feedwater system and decay heat being removed via the main condenser. | | | | The licensee is investigating the cause of the trip, but reported that | | numerous 125VDC ground alarms were received prior to the trip. The unit had | | been operating at reduced power because one of the reactor coolant pumps had | | been secured due to an oil leak. The NRC resident inspector has been | | informed of this event. | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ |Power Reactor |Event Number: 35848 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | FACILITY: SOUTH TEXAS REGION: 4 |NOTIFICATION DATE: 06/19/1999| | UNIT: [1] [] [] STATE: TX |NOTIFICATION TIME: 22:25[EDT]| | RXTYPE: [1] W-4-LP,[2] W-4-LP |EVENT DATE: 06/19/1999| +------------------------------------------------+EVENT TIME: 21:00[CDT]| | NRC NOTIFIED BY: ROBERT BRINKLEY |LAST UPDATE DATE: 06/19/1999| | HQ OPS OFFICER: BOB STRANSKY +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |JOHN PELLET R4 | |10 CFR SECTION: | | |DDDD 73.71 UNSPECIFIED PARAGRAPH | | | | | | | | | | | +-----+----------+-------+--------+-----------------+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ |1 N Y 100 Power Operation |100 Power Operation | | | | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | SAFEGUARDS SYSTEM DEGRADATION RELATED TO VITAL AREA BOUNDARY. COMPENSATORY | | MEASURES TAKEN UPON DISCOVERY. THE LICENSEE WILL INFORM THE NRC RESIDENT | | INSPECTOR. CONTACT THE OPERATIONS CENTER FOR ADDITIONAL DETAILS. | +------------------------------------------------------------------------------+
Page Last Reviewed/Updated Thursday, March 25, 2021
Page Last Reviewed/Updated Thursday, March 25, 2021