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Event Notification Report for March 14, 2000

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           03/13/2000 - 03/14/2000

                              ** EVENT NUMBERS **

36709  36790  36791  36792  

!!!!!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED  !!!!!!!
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|Fuel Cycle Facility                              |Event Number:   36709       |
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| FACILITY: PADUCAH GASEOUS DIFFUSION PLANT      |NOTIFICATION DATE: 02/19/2000|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 09:52[EST]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        02/18/2000|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        13:25[CST]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  03/13/2000|
|    CITY:  PADUCAH                  REGION:  3  +-----------------------------+
|  COUNTY:  McCRACKEN                 STATE:  KY |PERSON          ORGANIZATION |
|LICENSE#:  GDP-1                 AGREEMENT:  Y  |BRUCE JORGENSEN      R3      |
|  DOCKET:  0707001                              |                             |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  BEASLEY                      |                             |
|  HQ OPS OFFICER:  CHAUNCEY GOULD               |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|OCBB 76.120(c)(2)(ii)    EQUIP DISABLED/FAILS   |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
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                                   EVENT TEXT                                   
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| 24 HOUR NOTIFICATION - FAILURE OF THE UF6 RELEASE DETECTION SYSTEM           |
|                                                                              |
| At 1325 CST, on 2/18/00, the Plant Shift Superintendent (PSS) was notified   |
| of an air leak on the C-310 Cylinder Valve Closure System.  The function of  |
| this system is to close the cylinder valve in the case of an actuation of    |
| the UF6 Release Detection and Isolation System Low Voltage ("New") System at |
| the UF6 Withdrawal Stations.  TSR 2.3.4.1 requires this system to be         |
| operable while operating in mod 2.   At the time the leak was discovered,    |
| the air pressure on the Cylinder Valve Closure System was being maintained   |
| within allowed parameters.  However due to the size of the leak, it was      |
| questionable as to if the system could maintain enough air pressure to       |
| perform its intended safety function, if it were called upon.  After         |
| discussing with the C-310 building System Engineer, the PSS could not be     |
| provided with reasonable assurance of operability.  The UF6 Release          |
| detection System was declared inoperable by the PSS, and repair of the       |
| system was initiated.  TSR required LCO actions were implemented.  Repair of |
| the air leak was completed, and the UF6 Release Detection System was         |
| returned to Operable status at 1706 CST, on 2/18/00.                         |
|                                                                              |
| This event is reportable under 10 CFR 7B.120(c)(2) as an event in which      |
| equipment required by the TSR is disabled or fails to function as designed.  |
|                                                                              |
| The NRC Senior Resident inspector has been notified of this event and the    |
| DOE on site representative was also informed.                                |
|                                                                              |
| * * *  UPDATE ON 3/13/00 @ 1438 BY WALKER TO GOULD * * * RETRACTION          |
|                                                                              |
| THIS EVENT HAS BEEN RETRACTED.  Engineering Evaluation EN-C-826-00-018       |
| concluded that the capacity of the backup nitrogen supply regulator was      |
| sufficient to provide for this backflow and loss of system air, and still    |
| capable of providing flow to close two cylinder valves simultaneously.       |
| Thus, the system was capable of performing its intended safety function      |
| using nitrogen had it been called upon during the time of the subject event  |
| and the 10CFR76.120 reporting criteria were not met.  Given the results of   |
| this Engineering Evaluation, this event is being retracted.                  |
|                                                                              |
| The NRC Resident Inspector was informed and the Reg 3 RDO(Jacobson) and NMSS |
| EO(Smith) were notified.                                                     |
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|Fuel Cycle Facility                              |Event Number:   36790       |
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| FACILITY: PORTSMOUTH GASEOUS DIFFUSION PLANT   |NOTIFICATION DATE: 03/13/2000|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 22:00[EST]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        03/13/2000|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        19:57[EST]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  03/13/2000|
|    CITY:  PIKETON                  REGION:  3  +-----------------------------+
|  COUNTY:  PIKE                      STATE:  OH |PERSON          ORGANIZATION |
|LICENSE#:  GDP-2                 AGREEMENT:  N  |JOHN JACOBSON        R3      |
|  DOCKET:  0707002                              |THOMAS ESSIG         NMSS    |
+------------------------------------------------+JOSEPH GIITTER       IRO     |
| NRC NOTIFIED BY:  MCCLEARY                     |                             |
|  HQ OPS OFFICER:  CHAUNCEY GOULD               |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NBNL                     RESPONSE-BULLETIN      |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
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                                   EVENT TEXT                                   
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| 4 HOUR 91-01 BULLETIN RESPONSE                                               |
|                                                                              |
| The Plant Shift Superintendent(PSS) was notified of two seal test buggies on |
| the cell floor of the X-333 facility containing a vacuum pump whose oil      |
| reservoir volume was greater than the NCSA PLANT 069.A00 requirement of a 1  |
| quart reservoir.  Boundaries were placed around the buggies and the buggies  |
| were made inoperable to prevent use.  The NCSE allows 3 quarts for normal    |
| operations and an analyses for 5 quart reservoir for "abnormal operations."  |
| Therefore, the safety significance is low since the pumps supplied by the    |
| manufacturer have a reservoir volume of more than 3 quarts due to a design   |
| modification.  The site only had 4 pumps (two installed and two on the       |
| shelf) with this design modification.                                        |
|                                                                              |
| SAFETY SIGNIFICANCE OF EVENTS:                                               |
|                                                                              |
| The safety significance of this event is low. The NCSE evaluates a pump      |
| filled to a capacity of 5 quarts and shows the system to remain subcritical. |
| NCSE- PLANT 031 .E03, for similar carts, modeled a cart with a 5 quart       |
| vacuum pump adjacent to another cart and found that the system to be         |
| subcritical with a Keff +2q (sigma) of 0.841.                                |
|                                                                              |
|                                                                              |
| POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO[S] OF HOW            |
| CRITICALITY COULD OCCUR):                                                    |
|                                                                              |
| The Kinney model vacuum pump has a volume capacity of less than 4 quarts.    |
| For a criticality to occur, a cart with a pump with a capacity of 5 quarts   |
| would have to be used.  The chemical traps in front of the pump would have   |
| to be empty or saturated such that the pump oil becomes saturated with       |
| uranium, and a spacing violation would have to occur.                        |
|                                                                              |
|                                                                              |
| CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.):     |
|                                                                              |
| The controlled parameters in this NCSA are volume and interaction.           |
|                                                                              |
|                                                                              |
|                                                                              |
| ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL (INCLUDE PROCESS     |
| LIMIT AND % WORST CASE CRITICAL MASS):                                       |
|                                                                              |
| The carts are approved for use with 100% enriched material. The form of the  |
| material is uranium in oil. This system has been modeled and the Keff        |
| +2q(sigma) determined to be 0.841 for this upset.                            |
|                                                                              |
|                                                                              |
|                                                                              |
| NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION   |
| OF THE FAILURES OR DEFICIENCIES:                                             |
|                                                                              |
| The pump has been modified by the manufacturer to hold more than 3 quarts    |
|                                                                              |
|                                                                              |
|                                                                              |
| CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEM AND WHEN EACH WAS IMPLEMENTED:   |
|                                                                              |
| Established conditions as required by the Anomalous Condition procedure.     |
|                                                                              |
| The double contingency cannot be established within 4 hours and is           |
| reportable.                                                                  |
|                                                                              |
|                                                                              |
| The NRC Resident Inspector and DOE Representative were notified.             |
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|Power Reactor                                    |Event Number:   36791       |
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| FACILITY: ARKANSAS NUCLEAR         REGION:  4  |NOTIFICATION DATE: 03/14/2000|
|    UNIT:  [1] [] []                 STATE:  AR |NOTIFICATION TIME: 03:11[EST]|
|   RXTYPE: [1] B&W-L-LP,[2] CE                  |EVENT DATE:        03/14/2000|
+------------------------------------------------+EVENT TIME:        00:05[CST]|
| NRC NOTIFIED BY:  ALAN SMITH                   |LAST UPDATE DATE:  03/14/2000|
|  HQ OPS OFFICER:  STEVE SANDIN                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |DAVID GRAVES         R4      |
|10 CFR SECTION:                                 |BRUCE BOGER          NRR     |
|ARPS 50.72(b)(2)(ii)     RPS ACTUATION          |                             |
|APRE 50.72(b)(2)(vi)     OFFSITE NOTIFICATION   |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     M/R        Y       82       Power Operation  |0        Hot Shutdown     |
|                                                   |                          |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| UNIT 1 MANUALLY TRIPPED FOLLOWING A FAILURE OF THE MAIN TURBINE GOVERNOR     |
| VALVES CONTROL SYSTEM                                                        |
|                                                                              |
| "The Unit 1 Reactor was manually tripped following a failure of the main     |
| turbine governor valves control system. This failure resulted in the main    |
| turbine governor valves inadvertently going closed.  At the time of the      |
| event, Unit 1 was at 82% power and proceeding to 100% power following the    |
| completion of maintenance outage 1P-00-2.                                    |
|                                                                              |
| "Unit 1 has been stabilized in Hot Shutdown (550 degrees F, 2125 psig, and   |
| the reactor is subcritical).  No radioactive releases have occurred nor are  |
| any planned."                                                                |
|                                                                              |
| Prior to the transient the turbine governor valve position limit was acting  |
| erratically.  All control rods fully inserted.  Following the trip, primary  |
| pressure increased to 2300 psig.  Three(3) of  eight(8)  mainsteam (MS)      |
| safeties lifted and reseated on each MS header.  Also, Bus "1H1" which       |
| supplies power to two Reactor Coolant Pumps (RCPs) was slow in transferring  |
| to the startup transformer.  This resulted in both "P32A" and P32C" RCPs     |
| tripping.  The 1H1 bus remained energized during the transient.              |
|                                                                              |
| Unit 1 is currently removing decay heat using RCPs "P32B" and P32D" (one     |
| operating in each reactor coolant loop) with steam discharging to the Main   |
| Condenser.  All safety-related equipment  including the Emergency Diesel     |
| Generators (EDGs) is available, if needed.  I&C is investigating the cause   |
| of the governor valves' control system failure and the Relay Department is   |
| evaluating the slow bus transfer.                                            |
|                                                                              |
| The licensee informed the NRC Resident Inspector and the State of Arkansas.  |
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|Power Reactor                                    |Event Number:   36792       |
+------------------------------------------------------------------------------+
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| FACILITY: SEQUOYAH                 REGION:  2  |NOTIFICATION DATE: 03/14/2000|
|    UNIT:  [1] [] []                 STATE:  TN |NOTIFICATION TIME: 04:01[EST]|
|   RXTYPE: [1] W-4-LP,[2] W-4-LP                |EVENT DATE:        03/14/2000|
+------------------------------------------------+EVENT TIME:        00:35[EST]|
| NRC NOTIFIED BY:  BILL HARRIS                  |LAST UPDATE DATE:  03/14/2000|
|  HQ OPS OFFICER:  STEVE SANDIN                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |EDWARD MCALPINE      R2      |
|10 CFR SECTION:                                 |BRUCE BOGER          NRR     |
|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          N       0        Cold Shutdown    |0        Cold Shutdown    |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
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| MANUAL PHASE "A" AND CONTAINMENT VENT ISOLATION INITIATED DUE TO SHUTDOWN    |
| LOSS OF COOLANT ACCIDENT (LOCA).                                             |
|                                                                              |
| "Unit 1 was in Mode 5 with Cycle 10 refueling outage in progress.  At 0017   |
| on 3/14/00 with RCS temperature at 145 F and RCS pressure at 330 psig.  Unit |
| 1 entered Abnormal Operating Procedure R.02 (Shutdown LOCA) due to           |
| decreasing pressurizer level.  A manual Phase A and Containment Vent         |
| Isolation were initiated at 0035 as required by procedure. The loss of RCS   |
| coolant was initially contained in the Pressurizer Relief Tank (PRT) until   |
| the PRT rupture disc ruptured.  At 0125, AOP R.02 was completed and plant    |
| conditions were stabilized with RCS temperature at 156 F and RCS pressure at |
| 145 psig.  At present there is no RCS leakage, plant conditions are stable,  |
| and suspected cause is the RHR suction or discharge piping relief valve.     |
| Investigation is in progress."                                               |
|                                                                              |
| The transient lasted approximately 30 minutes.  The licensee suspects that   |
| when RCS pressure was lowered per the AOP, the relief valve reseated.  There |
| is no estimate of the lost RCS inventory at this time.                       |
|                                                                              |
| The licensee informed the NRC Resident Inspector.                            |
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