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Event Notification Report for April 20, 1999

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           04/19/1999 - 04/20/1999

                              ** EVENT NUMBERS **

35492  35603  35604  35605  35606  35607  35608  

!!!!!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED  !!!!!!!
+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   35492       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: FITZPATRICK              REGION:  1  |NOTIFICATION DATE: 03/20/1999|
|    UNIT:  [1] [] []                 STATE:  NY |NOTIFICATION TIME: 04:08[EST]|
|   RXTYPE: [1] GE-4                             |EVENT DATE:        03/20/1999|
+------------------------------------------------+EVENT TIME:        02:50[EST]|
| NRC NOTIFIED BY:  ALLEN                        |LAST UPDATE DATE:  04/19/1999|
|  HQ OPS OFFICER:  CHAUNCEY GOULD               +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |JACK MCFADDEN        R1      |
|10 CFR SECTION:                                 |                             |
|AIND 50.72(b)(2)(iii)(D) ACCIDENT MITIGATION    |                             |
|NLCO                     TECH SPEC LCO A/S      |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|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                                   
+------------------------------------------------------------------------------+
| THE "A" HPCI WAS DECLARED INOPERABLE, RESULTING IN A 7 DAY LCO ACTION        |
| STATEMENT.                                                                   |
|                                                                              |
| THE "A" HPCI ISOLATION LOGIC WAS DE-ENERGIZED, MAKING HPCI INOPERABLE, DUE   |
| TO A 120VDC BATTERY GROUND.  THIS CONDITION ALSO ACTUATED VALVES "23MOV-15"  |
| (INBOARD STEAM ISOLATION VALVE) AND "23MOV-58" (INBOARD TORUS SUCTION        |
| VALVE).  BOTH PENETRATIONS HAVE BEEN ISOLATED  AND DE-ENERGIZED WITHIN 1     |
| HOUR  AS REQUIRED BY TECH SPECS.  THE CAUSE OF THE GROUND IS UNKNOWN AND     |
| BEING INVESTIGATED.                                                          |
|                                                                              |
| THE RESIDENT INSPECTOR WILL BE NOTIFIED.                                     |
|                                                                              |
|                                                                              |
| ***Retraction on 04/19/99 at 1037 ET by Bob Steigerwald taken by             |
| MacKinnon****                                                                |
|                                                                              |
| This event is being retracted because of the following information because   |
| HPCI was capable of performing its intended safety function with the DC      |
| ground present.                                                              |
|                                                                              |
| Due to de-energization a portion of the HPCI system Containment Isolation    |
| Logic in order to isolate a ground on the 120 VDC bus HPCI was declared      |
| inoperable. Subsequent review of the DC ground determined that the ground    |
| was located on a surge suppressor for a signal to the plant computer (EPIC), |
| and had no effect on HPCI system operability.  The HPCI system isolation     |
| logic was taken out of service for the troubleshooting effort and the        |
| appropriate Limiting Condition for Operation was taken.  Therefore, since    |
| HPCI was capable of performing its intended safety function with the DC      |
| ground present, this event is not reportable and the notification is being   |
| retracted.  R1DO (Shanbaky) notified.                                        |
|                                                                              |
| The NRC Resident Inspector was not of this retraction by the licensee.       |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   35603       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: LIMERICK                 REGION:  1  |NOTIFICATION DATE: 04/19/1999|
|    UNIT:  [1] [2] []                STATE:  PA |NOTIFICATION TIME: 07:45[EDT]|
|   RXTYPE: [1] GE-4,[2] GE-4                    |EVENT DATE:        04/19/1999|
+------------------------------------------------+EVENT TIME:        04:38[EDT]|
| NRC NOTIFIED BY:  THOMAS J. TRAGEMANN          |LAST UPDATE DATE:  04/19/1999|
|  HQ OPS OFFICER:  DOUG WEAVER                  +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |DAN HOLODY           R1      |
|10 CFR SECTION:                                 |                             |
|ARPS 50.72(b)(2)(ii)     RPS ACTUATION          |                             |
|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  |100      Power Operation  |
|2     A          N       0        Refueling        |0        Refueling        |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| UNIT 2 REACTOR SCRAM FROM CONDITION FIVE                                     |
|                                                                              |
| On 4/19/99, at 0438, Unit 2 received an 'A' side half scram signal.  Unit 2  |
| was in OPCON 5 (refueling) and Unit 1 was at 100% power in OPCON 1.  The     |
| scram signal was a result of loss of voltage to 2AY160, the 'A' RPS power    |
| supply ('B' RPS was already blocked and a 'B' half scram was in).  Due to    |
| the loss of 2AY160 several isolations were received on Unit 2 including      |
| Reactor Water Cleanup, High Pressure Coolant Injection, Instrument Gas and   |
| HVAC  Groups (1B, 2A, 2C, 3, 5, 6A, 6B, 6C, 7A and 7B).  Unit 1 received     |
| groups 6A and 6B Containment Atmosphere Control isolations.  An              |
| investigation revealed an arcing bus bar on an RPS series output breaker     |
| (2AC248).  The bus breakers were opened causing the arcing to stop and       |
| maintenance is currently being planned.  All systems performed their         |
| intended function properly.                                                  |
|                                                                              |
| The licensee notified the NRC resident inspector.                            |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   35604       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: NINE MILE POINT          REGION:  1  |NOTIFICATION DATE: 04/19/1999|
|    UNIT:  [] [2] []                 STATE:  NY |NOTIFICATION TIME: 15:07[EDT]|
|   RXTYPE: [1] GE-2,[2] GE-5                    |EVENT DATE:        04/19/1999|
+------------------------------------------------+EVENT TIME:        11:15[EDT]|
| NRC NOTIFIED BY:  RICK LANGE                   |LAST UPDATE DATE:  04/19/1999|
|  HQ OPS OFFICER:  DICK JOLLIFFE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |MOHAMED SHANBAKY     R1      |
|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   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| - NEW YORK DEPARTMENT OF ENVIRONMENTAL CONSERVATION NOTIFIED OF 11 GALLON    |
| OIL SPILL -                                                                  |
|                                                                              |
| AT 1115 ON 04/19/99, THE LICENSEE NOTIFIED THE NEW YORK STATE DEPARTMENT OF  |
| ENVIRONMENTAL CONSERVATION THAT APPROXIMATELY 11 GALLONS OF HYDRAULIC OIL    |
| HAD SPILLED ON PAVED AND UNPAVED AREAS FROM A RUPTURED FORKLIFT HYDRAULIC    |
| LINE.  THE LICENSEE CLEANED UP THE OIL AND REMOVED THE AFFECTED SOIL.        |
|                                                                              |
| THE LICENSEE PLANS TO INFORM THE NRC RESIDENT INSPECTOR.                     |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   35605       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: LIMERICK                 REGION:  1  |NOTIFICATION DATE: 04/19/1999|
|    UNIT:  [1] [2] []                STATE:  PA |NOTIFICATION TIME: 16:06[EDT]|
|   RXTYPE: [1] GE-4,[2] GE-4                    |EVENT DATE:        04/19/1999|
+------------------------------------------------+EVENT TIME:        15:45[EDT]|
| NRC NOTIFIED BY:  GREG SOSSON                  |LAST UPDATE DATE:  04/19/1999|
|  HQ OPS OFFICER:  DICK JOLLIFFE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |MOHAMED SHANBAKY     R1      |
|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        Refueling        |0        Refueling        |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| - PLANT SECURITY REPORT -                                                    |
|                                                                              |
| UNESCORTED ACCESS INAPPROPRIATELY GRANTED TO THE PLANT PROTECTED AREA.       |
| COMPENSATORY MEASURES TAKEN IMMEDIATELY UPON DISCOVERY.  REFER TO THE HOO    |
| LOG FOR ADDITIONAL DETAILS.                                                  |
|                                                                              |
| THE LICENSEE PLANS TO INFORM THE NRC RESIDENT INSPECTOR.                     |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Fuel Cycle Facility                              |Event Number:   35606       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: PADUCAH GASEOUS DIFFUSION PLANT      |NOTIFICATION DATE: 04/19/1999|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 16:54[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        04/18/1999|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        16:00[CDT]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  04/19/1999|
|    CITY:  PADUCAH                  REGION:  3  +-----------------------------+
|  COUNTY:  McCRACKEN                 STATE:  KY |PERSON          ORGANIZATION |
|LICENSE#:  GDP-1                 AGREEMENT:  Y  |MELVYN LEACH         R3      |
|  DOCKET:  0707001                              |JOHN SURMEIER        NMSS    |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  FRANK CAGE                   |                             |
|  HQ OPS OFFICER:  DICK JOLLIFFE                |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NBNL                     RESPONSE-BULLETIN      |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| - NRC Bulletin 91-01, 24 hour report:  Vacuum hose found wrapped around a    |
| HEPA vacuum cleaner -                                                        |
|                                                                              |
| A HEPA vacuum cleaner was discovered in a containment pan on top of the      |
| C-337 Surge Drum Room with the vacuum hose wrapped around it in violation of |
| Nuclear Criticality Safety Approval NCSA GEN-04. The purpose of the          |
| requirement is to prevent fissile material which may be present inside the   |
| hose due to a clog from interacting with the material within the vacuum      |
| cleaner.  No information is available to indicate the hose is clogged,       |
| therefore, it is assumed that it is not clogged.  This information was       |
| requested, however, the personnel who last used the vacuum was not           |
| available.                                                                   |
|                                                                              |
| SAFETY SIGNIFICANCE OF EVENTS:                                               |
| Double contingency was not maintained because the hose was not adequately    |
| spaced from the vacuum.  A control which was relied upon for double          |
| contingency was violated.  If both controls were lost, the configuration     |
| would still be subcritical; however, the evaluation does not credit          |
| additional controls for double contingency.                                  |
|                                                                              |
| POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO[S] OF HOW            |
| CRITICALITY COULD OCCUR):                                                    |
| If both controls were lost, the configuration would still be subcritical.    |
| For a criticality to be possible, both controls would have to be lost and    |
| the vacuum hose would need to be greater than 12 feet in length and the      |
| entire hose full of fissile material.  Additionally, the hose would have to  |
| be wrapped around the vacuum cleaner.  The hose in use was less than 12 feet |
| in total length.                                                             |
|                                                                              |
| CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC):      |
| InteractIon.                                                                 |
|                                                                              |
| ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL (INCLUDE PROCESS     |
| LIMIT AND % WORST CASE CRITICAL MASS):                                       |
| Estimated amount of uranium:  Less than 80 pounds.                           |
| Enrichment:  Less than 2.0 wt% U-235.                                        |
| Form of licensed material:  UO2F2.                                           |
| Process limit:  600 pounds uranium.                                          |
|                                                                              |
| NUCLEAR CRITICALITY SAFETY CONTROLS INVOLVED AND THEIR IMPACT ON DOUBLE      |
| CONTINGENCY:                                                                 |
| Double contingency for this scenario is established by implementing two      |
| controls on Interaction.                                                     |
|                                                                              |
| The first leg of double contingency is based on requiring a clogged vacuum   |
| hose to be disconnected from the vacuum and placed in a 5.5 gallon waste     |
| drum and handled as waste.  Handling the clogged hose as waste will ensure   |
| the minimum spacing is observed and limit/control interaction between the    |
| hose and vacuum.  There is no indication that the hose is clogged;           |
| therefore, this control is considered intact.                                |
|                                                                              |
| The second leg of double contingency is based on a control to prevent the    |
| hose from being wrapped around the vacuum. The purpose of this requirement   |
| is to prevent interaction between the vacuum and other fissile material      |
| which may be contained within the hose in the event there is a clog within   |
| the hose and the clog is not discovered or properly handled.  This control   |
| was violated.                                                                |
|                                                                              |
| Since double contingency was based on two controls on interaction and one    |
| control was violated, double contingency was not maintained.                 |
|                                                                              |
| EXCLUSION ZONE AND POSTINGS:                                                 |
| The area should be posted with an NCS requirement sign in accordance with    |
| CP2-EG-NS1031 which states the following:                                    |
| - This area contains improperly stored HEPA vacuum hoses.                    |
| - Do not move fissile/potentially fissile material into or within this zone  |
| without NCS consent.                                                         |
| - Maintain a minimum 2 feet edge-to-edge spacing from any other              |
| fissile/potentially fissile material.                                        |
|                                                                              |
| CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED:  |
| Corrective actions will be provided via remediation guide #NCS-RG-99-009.    |
|                                                                              |
| PGDP Problem Report #ATRC-99-2201; PGDP Event Report #PAD-1999-028; Incident |
| Report #NCS-INC-99-021                                                       |
|                                                                              |
| This event is being reported as a 24 hour Event Notification as an NRC       |
| Bulletin 91-01 Report.                                                       |
|                                                                              |
| The NRC Resident Inspector has been notified of this event.                  |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Fuel Cycle Facility                              |Event Number:   35607       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: PORTSMOUTH GASEOUS DIFFUSION PLANT   |NOTIFICATION DATE: 04/19/1999|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 17:55[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        04/19/1999|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        14:00[EDT]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  04/19/1999|
|    CITY:  PIKETON                  REGION:  3  +-----------------------------+
|  COUNTY:  PIKE                      STATE:  OH |PERSON          ORGANIZATION |
|LICENSE#:  GDP-2                 AGREEMENT:  N  |MELVYN LEACH         R3      |
|  DOCKET:  0707002                              |JOHN SURMEIER        NMSS    |
+------------------------------------------------+CHARLES MILLER       IRO     |
| NRC NOTIFIED BY:  RICK LARSON                  |                             |
|  HQ OPS OFFICER:  DICK JOLLIFFE                |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NBNL                     RESPONSE-BULLETIN      |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| - NRC BULLETIN 91-01, 4 HOUR REPORT:  ABANDONED COLD TRAPS MAY BE COVERED BY |
| AN  NCSA -                                                                   |
|                                                                              |
| DURING A WALKDOWN OF NUCLEAR CRITICALITY SAFETY APPROVAL NCSA_PLANT088.A00,  |
| "STORAGE of  ABANDONED EQUIPMENT" FOR IMPLEMENTATION, IT WAS DETERMINED THAT |
| ABANDONED COLD TRAPS LOCATED IN BUILDINGS X-342 AND X-343 MAY APPLY TO THIS  |
| NCSA AND SHOULD HAVE BEEN REPORTED IN JANUARY, 1999 UNDER NRC EVENT REPORT   |
| #35275.  AT THIS TIME, THERE IS NO PROOF THAT THIS EQUIPMENT BELONGS TO DOE  |
| AND WITHOUT THIS DOCUMENTATION, THE MATERIAL FALLS UNDER USEC CONTROL AND    |
| SHOULD BE COVERED BY AN NCSA.  SINCE THIS EQUIPMENT IS NOT COVERED BY AN     |
| NCSA, IT IS REPORTABLE AS A CRITICALITY CONTROL 4 HOUR BULLETIN 91-01        |
| REPORT.  THE PLANT FOLLOWED ITS PROCEDURE FOR ANOMALOUS NCSA CONDITIONS.     |
| FURTHER EVALUATIONS ARE IN PROGRESS TO DETERMINE IF THIS ABANDONED EQUIPMENT |
| MEETS THE FISSILE MATERIAL LIMITS.  THE FISSILE MATERIAL LIMIT OF 15 GRAMS   |
| OF U-235 BY PLANT PROCEDURES REQUIRES AN NCSA.                               |
|                                                                              |
| SAFETY SIGNIFICANCE OF EVENTS:                                               |
| NO COLD TRAP CYLINDERS ARE INSTALLED.  PIPING IS LESS THAN OR EQUAL TO 2     |
| INCHES IN DIAMETER WHICH IS A FAVORABLE GEOMETRY.  CHEMICAL TRAPS ARE SEALED |
| AND NOT EXPOSED TO ANY WATER OR MODERATOR SOURCE.                            |
|                                                                              |
| POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO[S] OF HOW            |
| CRITICALITY COULD OCCUR):                                                    |
| PATHWAY ONLY EXISTS IF MORE THAN 13 POUNDS OF UO2F4 EXISTS IN A SINGLE ITEM  |
| AND WATER IS ALLOWED TO OPTIMALLY MODERATE AND REFLECT A SPHERE OF THIS      |
| MATERIAL.                                                                    |
|                                                                              |
| CONTROLLED PARAMETERS (MASS, MODERATION. GEOMETRY, CONCENTRATION, ETC.):     |
| NO NCSA HAS BEEN WRITTEN FOR THIS EQUIPMENT.  HOWEVER, NCSA_088 ESTABLISHES  |
| MASS AND MODERATION CONTROLS FOR THIS EQUIPMENT.  PLANT_088 IS NOT           |
| IMPLEMENTED AT THIS TIME.                                                    |
|                                                                              |
| ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL (INCLUDE PROCESS     |
| LIMIT AND % WORST CASE CRITICAL MASS):                                       |
| EXPECTED TO BE LESS THAN 350 GRAMS OF U-235 IN UO2F2 FORM AT 5.0%            |
| ENRICHMENT.                                                                  |
|                                                                              |
| NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION   |
| OF THE FAILURES OR DEFICIENCIES:                                             |
| NO NCS CONTROLS ESTABLISHED.                                                 |
|                                                                              |
| CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEM AND WHEN EACH WAS IMPLEMENTED:   |
| AT 1710, THE AREAS WERE BOUNDARY OFF PER OUR PROCEDURES.                     |
|                                                                              |
| THERE WAS NO LOSS OF HAZARDOUS OR RADIOACTIVE MATERIAL NOR RADIOACTIVE OR    |
| RADIOLOGICAL CONTAMINATION EXPOSURE AS A RESULT OF THIS EVENT.               |
|                                                                              |
| PTS-1 999-029; PR-PTS-99-02208.                                              |
|                                                                              |
| THE NRC RESIDENT INSPECTOR HAS BEEN NOTIFIED OF THIS EVENT.                  |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Fuel Cycle Facility                              |Event Number:   35608       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: PADUCAH GASEOUS DIFFUSION PLANT      |NOTIFICATION DATE: 04/19/1999|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 22:51[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        04/19/1999|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        09:50[CDT]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  04/19/1999|
|    CITY:  PADUCAH                  REGION:  3  +-----------------------------+
|  COUNTY:  McCRACKEN                 STATE:  KY |PERSON          ORGANIZATION |
|LICENSE#:  GDP-1                 AGREEMENT:  Y  |MELVYN LEACH         R3      |
|  DOCKET:  0707001                              |JOHN SURMEIER        NMSS    |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  KEVIN BEASLEY                |                             |
|  HQ OPS OFFICER:  DICK JOLLIFFE                |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NBNL                     RESPONSE-BULLETIN      |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| - NRC BULLETIN 91-01, 24 HOUR REPORT: Two exempted parts contained visible   |
| quantities of uranium -                                                      |
|                                                                              |
| At 0910 CDT on 04/19/99, while performing a walk-through of the disassembly  |
| area of building C-400, two exempted parts were discovered to contain        |
| visible quantities of uranium. The parts were exempted in violation of       |
| requirement 3.2.11 of Nuclear Criticality Safety Approval NCSA 400.007.00    |
| which allows NCS exemption of decontaminated parts based on two independent, |
| visual inspections indicating they contain no visible uranium contamination. |
| The purpose of this requirement is to ensure uranium contaminated parts are  |
| not exempted from NCS controls prior to proper inspection and verification   |
| of no visible uranium contamination. The independent visual inspections were |
| performed in error.                                                          |
|                                                                              |
| SAFETY SIGNIFICANCE OF EVENTS:                                               |
| The amount of visible uranium contamination was limited to a small quantity  |
| In a crevice of the parts. Although the amount of fissile material present   |
| is far below a safe mass, double contingency was not maintained since the    |
| Independent visual inspections were performed in error.  Both controls       |
| relied upon for verification of no visible uranium mass were violated,       |
|                                                                              |
| POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO[S] OF HOW            |
| CRITICALITY COULD OCCUR):                                                    |
| In order for a criticality to be possible, the seal parts would have to      |
| contain greater than a safe mass of uranium and form a critical              |
| configuration.                                                               |
|                                                                              |
| CONTROLLED PARAMETERS (MASS, MODERATION. GEOMETRY, CONCENTRATION, ETC.):     |
| Mass                                                                         |
|                                                                              |
| ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL (INCLUDE PROCESS     |
| LIMIT AND % WORST CASE CRITICAL MASS):                                       |
| Less than 80 pounds of uranium; less than 2.0 wt %; UO2F2; (process limit:   |
| 2.0 wt %;  worst case critical mass: 600 pounds of uranium)                  |
|                                                                              |
| NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION   |
| OF THE FAILURES OR DEFICIENCIES:                                             |
| Double contingency for this scenario is established by implementing two      |
| controls on mass.                                                            |
|                                                                              |
| The first leg of double contingency is based upon inspection results         |
| Indicating there is no visible uranium present on seal parts prior to NCS    |
| exemption. This is controlled by performing a visual inspection of the seal  |
| parts indicating no visible uranium contamination. The documentation for the |
| inspection indicated no visual uranium contamination. The seal parts         |
| contained visible quantities of uranium contamination: therefore, this       |
| control was violated and the process condition exceeded.                     |
|                                                                              |
| The second leg of double contingency relies upon a second independent,       |
| visual inspection verifying there is no visible uranium present on seal      |
| parts prior to NCS exemption.  This is controlled by performing a second     |
| independent visual inspection of the seal parts indicating no visible        |
| uranium contamination.  The documentation for the second independent         |
| inspection also indicated no visual uranium contamination.  The seal parts   |
| contained visible quantities of uranium contamination: therefore, this       |
| control was violated and the process condition exceeded.                     |
|                                                                              |
| Since both controls relied upon for double contingency were violated, double |
| contingency was not maintained.                                              |
|                                                                              |
| CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED:  |
| NCSA GEN-01 was immediately implemented upon discovery of the problem to     |
| prevent further actions until NCS approved corrective actions can be         |
| implemented.                                                                 |
|                                                                              |
| This event is being categorized as a 24-hour event, in accordance with       |
| Safety Analysis Report Table 6.9-1, Criteria A.4.a and NRC Bulletin 91-01,   |
| Supplement 1 report.                                                         |
|                                                                              |
| The NRC Senior Resident Inspector has been notified of this event.           |
|                                                                              |
| PGDP Problem Report No. ATR-99-2212;  PGDP Event Report No. PAD-I999-029.    |
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Page Last Reviewed/Updated Thursday, March 25, 2021