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Event Notification Report for October 24, 2000

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           10/23/2000 - 10/24/2000

                              ** EVENT NUMBERS **

37441  37450  37451  

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|Fuel Cycle Facility                              |Event Number:   37441       |
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| FACILITY: WESTINGHOUSE ELECTRIC CORPORATION    |NOTIFICATION DATE: 10/19/2000|
|   RXTYPE: URANIUM FUEL FABRICATION             |NOTIFICATION TIME: 08:53[EDT]|
| COMMENTS: LEU CONVERSION (UF6 to UO2)          |EVENT DATE:        10/18/2000|
|           COMMERCIAL LWR FUEL                  |EVENT TIME:        09:30[EDT]|
|                                                |LAST UPDATE DATE:  10/23/2000|
|    CITY:  COLUMBIA                 REGION:  2  +-----------------------------+
|  COUNTY:  RICHLAND                  STATE:  SC |PERSON          ORGANIZATION |
|LICENSE#:  SNM-1107              AGREEMENT:  Y  |CAUDLE JULIAN        R2      |
|  DOCKET:  07001151                             |BRIAN SMITH          NMSS    |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  JIM HEATH                    |                             |
|  HQ OPS OFFICER:  JOHN MacKINNON               |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NBNL                     RESPONSE-BULLETIN      |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
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                                   EVENT TEXT                                   
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| FAILURE OF VAPORIZE LEVEL PROBE IN "3A" VAPORIZER                            |
|                                                                              |
| NRC BULLETIN 91-01 24 HOUR NOTIFICATION                                      |
|                                                                              |
| Periodic testing of the condensate level detection system in the 3A          |
| vaporizer steam chest determined that the system could not perform its       |
| intended function due to blockage in the system by loose debris.  Further    |
| investigation determined that paint flaked from the recently processed       |
| cylinder and collected in the bottom of the vaporizer.  However, the debris  |
| did not block the main condensate removal drain which allowed condensate to  |
| be removed from the vaporizer, so there was no condensate accumulation.      |
|                                                                              |
| The vaporizer bottom was cleaned and the level detection system was checked. |
| The system responded correctly.                                              |
|                                                                              |
| SAFETY SIGNIFICANCE OF EVENTS:                                               |
|                                                                              |
| No contingency occurred.  No accumulation of water in the bottom of the      |
| vaporizer occurred.  No SNM was involved.                                    |
|                                                                              |
| CONTROLLED PARAMETER:                                                        |
|                                                                              |
| Mass and moderator are the controlled parameters for the vaporizer.          |
|                                                                              |
| ESTIMATED AMOUNT, ENRICHMENT, FORM of LICENSED MATERIAL:                     |
|                                                                              |
| Cylinders heated in the vaporizer contain uranium hexafluoride gas with a    |
| uranium-235 enrichment less than 5.0 weight percent. No SNM  was involved in |
| this incident since uranium hexafluoride was contained at all times within   |
| the uranium hexafluoride piping system.                                      |
|                                                                              |
| NUCLEAR CRITICALITY SAFETY CONTROL(s) OR CONTROLLED SYSTEM(s) AND            |
| DESCRIPTION OF THE FAILURES OR DEFICIENCIES:                                 |
|                                                                              |
| The condensate level detection system in the 3A vaporizer was rendered       |
| inoperable as a result of a drain line that was blocked by debris which came |
| from the most recently processed cylinder.                                   |
|                                                                              |
| CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED:  |
|                                                                              |
| The debris in the 3A vaporizer was removed and proper functioning of the     |
| level detection system was verified.  The 3A vaporizer was released for      |
| restart on October 19, 2000 at 0730 hours.  Other vaporizers not in use at   |
| the time of the incident were checked for proper functioning of the level    |
| detection system; each system responded correctly.   Other vaporizers in use |
| at the time were subject to increased-frequency checks to verify proper      |
| functioning of the condensate removal system; all vaporizers were draining   |
| properly.  In addition, the condensate level detection system for in-use     |
| vaporizers will be function-tested immediately after the uranium             |
| hexafluoride cylinder currently being processed is removed.                  |
|                                                                              |
|                                                                              |
| * * * UPDATE ON 10/23/00 @ 1210 BY HEATH TO GOULD * * *                      |
|                                                                              |
| Reason for submitting supplemental information:                              |
|                                                                              |
| Supplemental information is submitted to provide further information on the  |
| as found condition and to clarify the safety significance of the event.      |
|                                                                              |
| Double Contingency Protection:                                               |
|                                                                              |
| 30B UF6 cylinders are heated in the vaporizers with saturated steam. The     |
| steam is removed via a condensate removal system.  Double contingency        |
| protection for the vaporizers is based on mass and moderator control. Mass   |
| control consists of controls to prevent and detect an uncontrolled release   |
| of UF6 inside the vaporizer. Moderator control consists of controls to       |
| detect accumulation of moderator (specifically condensate) and prevent the   |
| accumulation of moderator in the bottom of the vaporizer.                    |
|                                                                              |
| As Found Condition:                                                          |
|                                                                              |
| Two drains are present in the bottom of each vaporizer which allow steam to  |
| enter the condensate removal system.  Each drain has an individual drain     |
| screen.  A larger removable debris screen rests in the bottom of the         |
| vaporizer above the two individual drain screens.  One drain flows through a |
| pot in which reside the high and high-high level probes.  The second drain   |
| proceeds directly to the condensate system.  In this event the screen which  |
| covers the drain which flows to the level pot was obstructed with paint      |
| residue, thereby isolating the level probes.  As a result of the isolation   |
| of the level probes, the ability to detect high level was lost.  However, at |
| no time was the condensate removal path closed.  There was no accumulation   |
| of water in the vaporizer and no SNM was present.                            |
|                                                                              |
| The cylinder from which the paint residue came was provided by Urenco.       |
| Urenco has been advised by this facility of the situation.  Prior to         |
| processing, the paint showed no indication of being defective. The paint was |
| not chipped, peeling, bubbling from the surface, discolored, or otherwise    |
| distinguishable as flawed.                                                   |
|                                                                              |
| It is also very likely that the plugging of the drain occurred as a result   |
| of the functional test which detected it.  The functional test of the        |
| vaporizer level probes is performed by filling the bottom of the empty       |
| vaporizer with water from a hose.  During steady state operation the         |
| expected flow rate of condensate through a vaporizer is on the order of 1.48 |
| gallons per hour.   As was described earlier, the larger debris screen rests |
| above the two drains. The seal along the bottom perimeter of the debris      |
| screen is not air or water tight and need not be due to the fact that it     |
| sees a low flow rate of steam and not a flow of liquid.  During the          |
| functional test, it is likely the paint debris was sluiced underneath the    |
| debris screen by the relatively high flow rate of water which is used for    |
| the test. Notification was nevertheless made due to the fact that there is a |
| small possibility that the vaporizer was operated in this condition.         |
|                                                                              |
|                                                                              |
| Conclusions related to safety significance:                                  |
|                                                                              |
| * Loss of double contingency protection may have occurred.                   |
| * No UF6 leaks occurred in the vaporizer.  No failure of mass controls       |
| occurred.  No SNM was involved.                                              |
| * The condensate flow path from the vaporizer was not blocked.  No moderator |
| accumulated in the vaporizer                                                 |
| * At no time was there any risk to the health or safety of any employee or   |
| member of the public. No exposure to  hazardous material was involved.       |
| * The safety significance of this event is evaluated to be low.              |
|                                                                              |
|                                                                              |
| The Reg 2 RDO(Belise) and the MNSS EO(Schnieder) were notified               |
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|Power Reactor                                    |Event Number:   37450       |
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| FACILITY: SAINT LUCIE              REGION:  2  |NOTIFICATION DATE: 10/23/2000|
|    UNIT:  [1] [2] []                STATE:  FL |NOTIFICATION TIME: 13:31[EDT]|
|   RXTYPE: [1] CE,[2] CE                        |EVENT DATE:        10/23/2000|
+------------------------------------------------+EVENT TIME:        13:00[EDT]|
| NRC NOTIFIED BY:  BREEN                        |LAST UPDATE DATE:  10/23/2000|
|  HQ OPS OFFICER:  CHAUNCEY GOULD               +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |AL BELISLE           R2      |
|10 CFR SECTION:                                 |                             |
|APRE 50.72(b)(2)(vi)     OFFSITE NOTIFICATION   |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|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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| THE LICENSEE MADE NOTIFICATION TO FLORIDA FISH AND WILDLIFE CONSERVATION     |
| COMMISSION                                                                   |
|                                                                              |
| This notification was made due to a live loggerhead turtle being found in    |
| the intake net.  The turtle was not in very good condition.  It will be sent |
| off site for rehabilitation.                                                 |
|                                                                              |
| The NRC Resident Inspector was notified.                                     |
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|Power Reactor                                    |Event Number:   37451       |
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| FACILITY: DIABLO CANYON            REGION:  4  |NOTIFICATION DATE: 10/23/2000|
|    UNIT:  [] [2] []                 STATE:  CA |NOTIFICATION TIME: 21:25[EDT]|
|   RXTYPE: [1] W-4-LP,[2] W-4-LP                |EVENT DATE:        10/23/2000|
+------------------------------------------------+EVENT TIME:        16:37[PDT]|
| NRC NOTIFIED BY:  BAHNER                       |LAST UPDATE DATE:  10/23/2000|
|  HQ OPS OFFICER:  CHAUNCEY GOULD               +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |GREG PICK            R4      |
|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  |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| PLANT HAD AUTO START OF ALL THREE DIESEL GENERATORS DUE TO PERSONNEL ERROR   |
|                                                                              |
| Startup Power was being cleared to Unit 1 for refueling outage maintenance.  |
| Part of the clearance was to open switch 211-1 for Unit 1 Startup            |
| Transformer.  Operators inadvertently opened switch 211-2 for Unit 2 Startup |
| Transformer.  This caused all three Unit 2 Diesel Generators (D/G) to start  |
| on loss of Startup Power signal. Starting of the D/G's is considered to be   |
| an ESF actuation and constitutes a 4 hour non-emergency report per           |
| 10CFR50.72(B)(2).  Startup Power was restored three minutes later and the    |
| D/G's returned to standby condition. The D/G's did not load on the bus and   |
| no other ESF systems were affected.                                          |
|                                                                              |
| The NRC Resident Inspector was notified.                                     |
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