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Event Notification Report for April 2, 2001

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           03/30/2001 - 04/02/2001

                              ** EVENT NUMBERS **

37875  37876  37877  37878  37879  

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|Power Reactor                                    |Event Number:   37875       |
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| FACILITY: SAINT LUCIE              REGION:  2  |NOTIFICATION DATE: 03/30/2001|
|    UNIT:  [1] [2] []                STATE:  FL |NOTIFICATION TIME: 10:08[EST]|
|   RXTYPE: [1] CE,[2] CE                        |EVENT DATE:        03/30/2001|
+------------------------------------------------+EVENT TIME:        10:05[EST]|
| NRC NOTIFIED BY:  CHARLES MARPLE               |LAST UPDATE DATE:  03/30/2001|
|  HQ OPS OFFICER:  FANGIE JONES                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |EDWARD MCALPINE      R2      |
|10 CFR SECTION:                                 |                             |
|*PRE 50.72(b)(2)(xi)     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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| OFFSITE NOTIFICATION - DEAD GREEN SEA TURTLE FOUND IN PLANT INTAKE           |
|                                                                              |
| At 1005 EST on 3/30/01, a notification was made to the Florida Fish and      |
| Wildlife Conservation Commission regarding a dead green sea turtle found in  |
| the plant's intake net.                                                      |
|                                                                              |
| The licensee notified the NRC resident inspector.                            |
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|Power Reactor                                    |Event Number:   37876       |
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| FACILITY: PALISADES                REGION:  3  |NOTIFICATION DATE: 03/31/2001|
|    UNIT:  [1] [] []                 STATE:  MI |NOTIFICATION TIME: 08:43[EST]|
|   RXTYPE: [1] CE                               |EVENT DATE:        03/31/2001|
+------------------------------------------------+EVENT TIME:        01:45[EST]|
| NRC NOTIFIED BY:  R A VINCENT                  |LAST UPDATE DATE:  03/31/2001|
|  HQ OPS OFFICER:  JOHN MacKINNON               +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |BRUCE BURGESS        R3      |
|10 CFR SECTION:                                 |                             |
|*DEG 50.72(b)(3)(ii)(A)  DEGRAD COND DURING OP  |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          N       0        Hot Standby      |0        Hot Standby      |
|                                                   |                          |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| BORIC ACID DEPOSIT DISCOVERED AROUND ONE CONTROL ROD DRIVE MECHANISM (CRDM)  |
| MECHANICAL SEAL HOUSING.                                                     |
|                                                                              |
| During an inspection of the reactor head area following shutdown for a       |
| refueling outage, a boric acid deposit and a small amount of water were      |
| found on one (of 45) CRDM mechanical seal housing.  These deposits may       |
| potentially indicate reactor coolant system through-wall leakage.  Further   |
| investigation will be performed following plant cooldown to determine        |
| whether deposits resulted from through-wall leakage or mechanical joint      |
| leakage, and appropriate corrective actions will be taken prior to startup   |
| from the refueling outage.                                                   |
|                                                                              |
| Boric acid was spread over a one square foot area and there is not any       |
| significant buildup of boric acid deposits.                                  |
|                                                                              |
| The NRC Resident Inspector was notified of this event by the licensee.       |
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|Power Reactor                                    |Event Number:   37877       |
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| FACILITY: COOPER                   REGION:  4  |NOTIFICATION DATE: 03/31/2001|
|    UNIT:  [1] [] []                 STATE:  NE |NOTIFICATION TIME: 10:17[EST]|
|   RXTYPE: [1] GE-4                             |EVENT DATE:        03/30/2001|
+------------------------------------------------+EVENT TIME:        18:16[CST]|
| NRC NOTIFIED BY:  OHRABLO                      |LAST UPDATE DATE:  03/31/2001|
|  HQ OPS OFFICER:  JOHN MacKINNON               +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |DAVE LOVELESS        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  |
|                                                   |                          |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| Safeguards system degradation related to detection alarms being inoperable.  |
| Immediate compensatory measures taken upon discovery.  The licensee will     |
| notify the NRC Resident Inspector.                                           |
|                                                                              |
| Call Headquarters Operation Officer for further details.                     |
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|Power Reactor                                    |Event Number:   37878       |
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| FACILITY: PALO VERDE               REGION:  4  |NOTIFICATION DATE: 03/31/2001|
|    UNIT:  [1] [] []                 STATE:  AZ |NOTIFICATION TIME: 17:05[EST]|
|   RXTYPE: [1] CE,[2] CE,[3] CE                 |EVENT DATE:        03/31/2001|
+------------------------------------------------+EVENT TIME:        10:58[MST]|
| NRC NOTIFIED BY:  DAN MARKS                    |LAST UPDATE DATE:  03/31/2001|
|  HQ OPS OFFICER:  CHAUNCEY GOULD               +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |DAVE LOVELESS        R4      |
|10 CFR SECTION:                                 |                             |
|*DEG 50.72(b)(3)(ii)(A)  DEGRAD COND DURING OP  |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          N       0        Hot Shutdown     |0        Hot Shutdown     |
|                                                   |                          |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| DISCOVERY OF  BORIC ACID RESIDUE BUILDUP ON RCS HOT LEG SPARE THERMOWELL     |
|                                                                              |
| On March 31, 2001, at approximately 10:58 mountain standard time (MST)       |
| engineering personnel performing preplanned visual examinations of reactor   |
| coolant system (RCS) piping in accordance with procedure requirements        |
| discovered boric acid residue on RCS hot leg spare thermowell 1JRCETW0121HB. |
| The visual observation was characterized as white streaks fanning out from   |
| the hot leg and continuing up the taper of the thermowell with some build-up |
| on the top of the tapered portion.  There were no signs of dripping,         |
| spraying, puddles of liquid, or liquid running down the nozzle or hot leg    |
| The residue appeared dry.                                                    |
|                                                                              |
| Technical Specifications (TS) Limiting Condition for Operation (LCO) 3.4.14  |
| permits no reactor coolant system (RCS) pressure boundary leakage and        |
| therefore, the discovery of leakage (presumed boric acid residue) from the   |
| hot leg thermowell was a degradation of a principal safety barrier.          |
| Therefore, the ENS notification of this event is in accordance with          |
| 10CFR50.72(b)(3)(ii).  The control room personnel entered LCO 3.4.14         |
| Condition B and are continuing to place the plant in Mode 5.                 |
|                                                                              |
| The RCS was being cooled down in preparation for Unit 1's ninth refueling    |
| outage.   At the time of discovery, the RCS was at approximately 300 degrees |
| F and 725 psia.                                                              |
|                                                                              |
| An investigation of this event will be conducted in accordance with the      |
| licensee's corrective action program.  The cracking of Alloy 600 components  |
| both at Palo Verde and industry-wide has been attributed to axially          |
| oriented, primary water stress corrosion cracking (PWSCC).   PWSCC is not    |
| considered a significant threat to the structural integrity of the RCS       |
| boundary or the thermowell as this type of cracking typically results only   |
| in small leaks,  The bases for this conclusion is that if PWSCC occurred at  |
| Palo Verde, the cracks would be predominately axial in orientation.  As in   |
| this case, the cracks would result in visibly detectable leakage that would  |
| be apparent during visual examinations, performed as part of walkdown        |
| inspections, before significant damage to the reactor coolant boundary       |
| occurred.                                                                    |
|                                                                              |
| Palo Verde has a program for replacing the Alloy 600 thermowells.  This      |
| thermowell was scheduled for replacement during this refueling outage.  The  |
| plans to replace the thermowell remain unchanged.                            |
|                                                                              |
| No ESF actuations occurred and none were required.  There were no            |
| structures, systems, or components that were inoperable at the time of       |
| discovery that contributed to this condition.  There were no failures that   |
| rendered a train of a safety system inoperable and no failures of components |
| with multiple functions were involved.  The event did not result in the      |
| release of radioactivity to the environment and did not adversely affect the |
| safe operation of the plant or health and safety of the public.              |
|                                                                              |
| The NRC Resident Inspector was notified.                                     |
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|Fuel Cycle Facility                              |Event Number:   37879       |
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| FACILITY: PADUCAH GASEOUS DIFFUSION PLANT      |NOTIFICATION DATE: 04/02/2001|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 03:42[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        04/01/2001|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        01:45[CST]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  04/02/2001|
|    CITY:  PADUCAH                  REGION:  3  +-----------------------------+
|  COUNTY:  McCRACKEN                 STATE:  KY |PERSON          ORGANIZATION |
|LICENSE#:  GDP-1                 AGREEMENT:  Y  |MICHAEL JORDAN       R3      |
|  DOCKET:  0707001                              |PATRICIA HOLAHAN     NMSS    |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  W. F. CAGE                   |                             |
|  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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| NRC BULLETIN 91-01,  24 HOUR NOTIFICATION INVOLVING REFRIGERANT-114 (R-114)  |
| NOT IMMEDIATELY SAMPLED TO DETERMINE MOISTURE CONTENT                        |
|                                                                              |
| On 03/31/01, R-114 was transferred from a rail car to the C-335 R-114 drain  |
| tank.  Following the transfer from the rail car it was determined that the   |
| C-335 R-114 drain tank was over the desired fill level and the decision was  |
| made to transfer the R-114 from the drain tank to C-335 Unit 4 Cell 9 R-114  |
| system.  The R-114 transfer to C-335 Unit 4 Cell 9 from the C-335 drain tank |
| was completed at 1740 CST on 03/31/01.  Following the 1900 shift change on   |
| 03/31/01 the C-335 building personnel questioned if the R-114 in C-335 Unit  |
| 4 Cell 9 should be sampled for moisture.  A review of the independent assay  |
| verification for C-335 Unit 4 Cell 9 revealed the assay was greater than 1   |
| wt% U235 assay and at 0145 CST on 04/01/01 it was determined that moisture   |
| sampling was required and the Plant Shift Superintendent was notified.  NCSA |
| CAS-011 requires that if R-114 is transferred to a cell that is above        |
| 1wt%U235 assay, the R-114 in the cell must be immediately sampled to         |
| determine the moisture content. Since the time between the transfer of the   |
| R-114 to the cell and the actual sampling was determined to not meet the     |
| NCSA requirement of immediate sampling and is therefore an NCS violation.    |
|                                                                              |
| SAFETY SIGNIFICANCE OF THE EVENT:                                            |
|                                                                              |
| Although a time limit to determine moisture is not possible, the control     |
| requires sampling to start immediately as defined in the TSR.  Sampling was  |
| delayed in violation of the control procedure.                               |
|                                                                              |
| POTENTIAL CRITICALITY PATHWAYS INVOLVED:                                     |
|                                                                              |
| In order for criticality to be possible, the following sequence must occur:  |
| Wet R-114 must leak into the process gas portion of the system which         |
| contains a larger that critical mass fissile deposit.  Sufficient time to    |
| enable the hydrogen of the deposit must pass and the deposit must be in a    |
| critical geometry for criticality to be possible.                            |
|                                                                              |
| 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 AND |
| % CASE CRITICAL MASS):                                                       |
|                                                                              |
| 1.5185 wt%U235                                                               |
|                                                                              |
| NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION   |
| OF THE FAILURES OR DEFICIENCIES:                                             |
|                                                                              |
| The first leg of double contingency is based on immediately sampling of      |
| R-114 for water content.  Actual moisture content was within acceptable      |
| specifications but the sample was not taken in accordance with the time      |
| requirement for control.  Specifically the control requires immediate        |
| sampling upon completion of the addition of R-114.                           |
|                                                                              |
| CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED:  |
|                                                                              |
|                                                                              |
| The R-114 was sampled at 0300 on 04/1/01 with the moisture level determined  |
| to be within specifications.                                                 |
|                                                                              |
| The NRC Resident Inspector was notified of this event by the Certificate     |
| Holder.                                                                      |
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