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Event Notification Report for May 26, 1999

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           05/25/1999 - 05/26/1999

                              ** EVENT NUMBERS **

35751  35763  35764  35765  35766  35767  35768  

!!!!!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED  !!!!!!!
+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   35751       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: HARRIS                   REGION:  2  |NOTIFICATION DATE: 05/21/1999|
|    UNIT:  [1] [] []                 STATE:  NC |NOTIFICATION TIME: 13:53[EDT]|
|   RXTYPE: [1] W-3-LP                           |EVENT DATE:        05/21/1999|
+------------------------------------------------+EVENT TIME:        10:16[EDT]|
| NRC NOTIFIED BY:  MARK ELLINGTON               |LAST UPDATE DATE:  05/25/1999|
|  HQ OPS OFFICER:  JOHN MacKINNON               +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |ANN BOLAND           R2      |
|10 CFR SECTION:                                 |                             |
|AESF 50.72(b)(2)(ii)     ESF ACTUATION          |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| INADVERTENT START OF THE 'B' CONTAINMENT SPRAY PUMP DUE TO AN INVALID START  |
| SIGNAL                                                                       |
|                                                                              |
| While performing the test of the Sequencer Block Circuit and Containment Fan |
| Cooler, Train 'B' (#OST- 1095) with the plant at 100% power, a maintenance   |
| technician placed multimeter leads on the wrong terminal points.  These      |
| terminal points were adjacent to the desired points. This caused an          |
| inadvertent start of the 'B' Containment Spray Pump.  This invalid actuation |
| was the result of an invalid signal generated by the maintenance technician. |
| Investigation indicates that no other components actuated.                   |
|                                                                              |
| The pump was aligned in standby and no flow was admitted to containment.     |
| The pump operated for approximately two minutes with adequate recirculation  |
| flow before it was secured.  No equipment damage occurred and the 'B'        |
| Containment Spray system is currently operable.  The licensee has            |
| conservatively determined that the pump start constitutes an ESF actuation.  |
|                                                                              |
| The NRC Resident Inspector was notified of this event by the licensee.       |
|                                                                              |
| * * * UPDATE AT 1817 ON 5/25/99 BY ELLINGTON, TAKEN BY WEAVER * * *          |
|                                                                              |
| On May 21, 1999, Harris Nuclear Plant performed a four hour non-emergency    |
| notification for an  ESF actuation on the inadvertent starting of the  B     |
| Containment  Spray Pump.   Harris Nuclear Plant has subsequently determined  |
| that no other components actuated nor would have actuated as a result of     |
| this event. The  B  Containment Spray Pump cannot by itself mitigate the     |
| consequences of an accident.  In order for the Containment Spray System to   |
| mitigate the consequences of an accident, a downstream header isolation      |
| valve would have been required to open. This header isolation valve remained |
| shut during this event. Harris Nuclear Plant has determined that this event  |
| was a single component actuation with no other components actuated and this  |
| single Component actuation could not have alone mitigated the consequences   |
| of an accident. Therefore, Harris Nuclear Plant retracts the May 21, 1999    |
| four hour non-emergency notification per guidance provided in NRC            |
| NUREG-1022, Revision 1 page 53.                                              |
|                                                                              |
| The licensee will inform the NRC resident inspector.  The HOO notified the   |
| R2DO (Decker).                                                               |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   35763       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: MILLSTONE                REGION:  1  |NOTIFICATION DATE: 05/25/1999|
|    UNIT:  [] [2] []                 STATE:  CT |NOTIFICATION TIME: 15:58[EDT]|
|   RXTYPE: [1] GE-3,[2] CE,[3] W-4-LP           |EVENT DATE:        05/25/1999|
+------------------------------------------------+EVENT TIME:        15:28[EDT]|
| NRC NOTIFIED BY:  MICHAEL BAIN                 |LAST UPDATE DATE:  05/25/1999|
|  HQ OPS OFFICER:  DOUG WEAVER                  +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |RICHARD CONTE        R1      |
|10 CFR SECTION:                                 |                             |
|ARPS 50.72(b)(2)(ii)     RPS ACTUATION          |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     M/R        Y       100      Power Operation  |0        Hot Standby      |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| MANUAL REACTOR TRIP BECAUSE OF A SECONDARY SIDE STEAM LEAK                   |
|                                                                              |
| The reactor was manually tripped from 100% power because of a steam leak in  |
| the 1A feedwater heater.  All control rods fully inserted.  Both motor       |
| driven Auxiliary Feedwater pumps were started and are maintaining water      |
| level in the steam generators.   Decay heat is being removed by use of the   |
| steam generator atmospheric reliefs.                                         |
| The MSIVs are shut.  The plant is stable in hot standby.                     |
|                                                                              |
| The steam leak was discovered when oscillations in the feedwater heater      |
| water level resulted in a main control board annunicator.  Personnel sent to |
| investigate the feedwater heater reported a steam leak in the pipe leading   |
| up to the flange to which the relief valve is connected.   Operators then    |
| manually tripped the reactor.                                                |
|                                                                              |
| Access to the turbine building is restricted while the feedwater heater is   |
| steaming down.  A 120 V instrument AC panel switched to an alternate power   |
| supply during the plant transient.  This had no effect on the plant's        |
| response.                                                                    |
|                                                                              |
| The licensee notified the NRC resident inspector and will notify state and   |
| local officials.                                                             |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   35764       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: THREE MILE ISLAND        REGION:  1  |NOTIFICATION DATE: 05/25/1999|
|    UNIT:  [1] [] []                 STATE:  PA |NOTIFICATION TIME: 17:03[EDT]|
|   RXTYPE: [1] B&W-L-LP,[2] B&W-L-LP            |EVENT DATE:        05/25/1999|
+------------------------------------------------+EVENT TIME:        16:21[EDT]|
| NRC NOTIFIED BY:  JOHN SCHORK                  |LAST UPDATE DATE:  05/25/1999|
|  HQ OPS OFFICER:  DOUG WEAVER                  +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |RICHARD CONTE        R1      |
|10 CFR SECTION:                                 |                             |
|AOUT 50.72(b)(1)(ii)(B)  OUTSIDE DESIGN BASIS   |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| PRESSURIZER SUPPORT BOLTS WOULD EXCEED ALLOWABLE STRESS DURING AN            |
| EARTHQUAKE                                                                   |
|                                                                              |
| At 1621 hours on May 25, 1999, utilizing preliminary calculations (not yet   |
| design verified), GPU Nuclear determined that a condition outside the design |
| basis of the plant exists at TMI-1 and that an immediate report to the NRC   |
| in accordance with 10 CFR 50.72(B)(i)(ii)(B) is required.                    |
|                                                                              |
| A review of the design of the bolts that insert into the Pressurizer Support |
| Lugs found that in the event of the Safe Shutdown Earthquake (the Maximum    |
| Hypothetical Earthquake (MHE)) the bolts would be exposed to loads in excess |
| of allowable stress as analyzed in the TMI-1 FSAR                            |
|                                                                              |
| The bolts have been determined to be operable utilizing building and         |
| equipment damping factors (7% / 7%) in accordance with NRC Regulatory Guide  |
| 1.61. However, the TMI-1 FSAR utilizes more conservative damping factors (2% |
| building / 2.5% equipment). When bolt load calculations are performed        |
| utilizing the FSAR factors, the MHE shear stress exceeds the allowable       |
| stress by approximately 25% and the MHE seismic stress slightly exceeds the  |
| allowable stress by approximately 1.5%.   However, when the calculations are |
| performed using the NRC Regulatory Guide 1.61 damping factors of 7% building |
| / 7% equipment, the MHE shear and MHE seismic stresses are well within the   |
| allowable stress.                                                            |
|                                                                              |
| GPU Nuclear intends to finalize the calculations and to resolve the          |
| non-conformance with the design basis as stated in the FSAR by either:       |
|                                                                              |
| Restoring the bolts to within the plant design basis via, the plant          |
| modification process or,                                                     |
|                                                                              |
| Revising the plant design basis via a license amendment.                     |
|                                                                              |
| This condition has been documented in the GPU Nuclear Corrective Action      |
| Program (CAP T1999-0264).                                                    |
|                                                                              |
| The licensee will inform the NRC resident inspector.                         |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   35765       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: NINE MILE POINT          REGION:  1  |NOTIFICATION DATE: 05/25/1999|
|    UNIT:  [] [2] []                 STATE:  NY |NOTIFICATION TIME: 17:27[EDT]|
|   RXTYPE: [1] GE-2,[2] GE-5                    |EVENT DATE:        05/25/1999|
+------------------------------------------------+EVENT TIME:        16:45[EDT]|
| NRC NOTIFIED BY:  RICK LANGE                   |LAST UPDATE DATE:  05/25/1999|
|  HQ OPS OFFICER:  DOUG WEAVER                  +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |RICHARD CONTE        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   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| HIGH PRESSURE CORE SPRAY (HPCS) INOPERABLE                                   |
|                                                                              |
| "HPCS is inoperable but available.  During an independent review of the  In  |
| Service Inspection (ISI) program plan it was found that 52 welds in the HPCS |
| system were improperly exempted from ISI requirements.  These welds are      |
| located between the Condensate Storage Tank (CST) and the HPCS pump suction  |
| valve (MOV101).  In addition, the weld inspections are required by ASME      |
| section XI.  Preparations are being made to perform the required ISI weld    |
| exams."                                                                      |
|                                                                              |
| The HPCS LCO is 14 days.   All other ECCS equipment is operable.             |
|                                                                              |
| The licensee informed the NRC resident inspector.                            |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   35766       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: PILGRIM                  REGION:  1  |NOTIFICATION DATE: 05/25/1999|
|    UNIT:  [1] [] []                 STATE:  MA |NOTIFICATION TIME: 21:29[EDT]|
|   RXTYPE: [1] GE-3                             |EVENT DATE:        05/25/1999|
+------------------------------------------------+EVENT TIME:        19:24[EDT]|
| NRC NOTIFIED BY:  MARTIN MANTENFEL             |LAST UPDATE DATE:  05/25/1999|
|  HQ OPS OFFICER:  DOUG WEAVER                  +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |RICHARD CONTE        R1      |
|10 CFR SECTION:                                 |                             |
|ADAS 50.72(b)(2)(i)      DEG/UNANALYZED COND    |                             |
|AINC 50.72(b)(2)(iii)(C) POT UNCNTRL RAD REL    |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          N       0        Refueling        |0        Refueling        |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| RCIC STEAM EXHAUST CHECK VALVES FAIL LEAK TEST                               |
|                                                                              |
| TWO IN SERIES REACTOR CORE ISOLATION COOLING (RCIC) STEAM EXHAUST CHECK      |
| VALVES FAILED THEIR LEAK TESTS.    THE LEAKAGE WAS IN EXCESS OF 10.1 GALLONS |
| PER MINUTE.   NO PRESSURE COULD BE ESTABLISHED IN THE LINE DURING THE TEST.  |
| THE PLANT IS SHUTDOWN IN REFUELING MODE SO RCIC IS NOT REQUIRED TO BE        |
| OPERABLE.   CORRECTIVE ACTION WILL BE TAKEN BEFORE STARTUP.                  |
|                                                                              |
| THE LICENSEE HAS NOTIFIED THE NRC RESIDENT INSPECTOR.                        |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|General Information or Other                     |Event Number:   35767       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| REP ORG:  WASHINGTON DEPARTMENT OF HEALTH      |NOTIFICATION DATE: 05/25/1999|
|LICENSEE:  UNIVERSITY OF WASHINGTON             |NOTIFICATION TIME: 23:52[EDT]|
|    CITY:  SEATTLE                  REGION:  4  |EVENT DATE:        11/21/1998|
|  COUNTY:                            STATE:  WA |EVENT TIME:        12:00[PDT]|
|LICENSE#:   WN-C001-1            AGREEMENT:  Y  |LAST UPDATE DATE:  05/25/1999|
|  DOCKET:                                       |+----------------------------+
|                                                |PERSON          ORGANIZATION |
|                                                |THOMAS ANDREWS       R4      |
|                                                |                     NMSS    |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  TERRY FRAZEE                 |                             |
|  HQ OPS OFFICER:  DOUG WEAVER                  |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NAGR                     AGREEMENT STATE        |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| This is notification of an event in Washington state as reported to the      |
| WA Department of Health, Division of Radiation Protection.                   |
|                                                                              |
| STATUS: new/closed                                                           |
|                                                                              |
| Licensee: UNIVERSITY OF WASHINGTON                                           |
| City and state: SEATTLE, WA                                                  |
| License number: WN-C001-1                                                    |
| Type of license: ACADEMIC BROAD SCOPE                                        |
| 9                                                                            |
| Date of Event: Unknown                                                       |
| Location of Event: Seattle, WA                                               |
| ABSTRACT: An "ownerless" surplus gas chromatograph (and detector cell)       |
| was being stored in a hallway at the University.  An inventory check in      |
| late December 1998 noted the unit was no longer in the hallway and was       |
| presumed to have been put into better storage.  By late January 1999,        |
| further checking had revealed that the unit probably had been taken to       |
| the UW Surplus Property Department.  Records indicated the unit probably     |
| had been sold at auction on November 21, 1998 (there is some uncertainty     |
| because some items having no apparent value were discarded prior to the      |
| auction).  The University RSO contacted the complete list of buyers in an    |
| attempt to recover the unit, however none of the buyers  remembered          |
| acquiring a gas chromatograph at the auction.  Some buyers also noted        |
| discarding items which had no apparent value immediately after the           |
| auction. The RSO has determined that the unit was most likely discarded      |
| in the trash in November either by UW Surplus Property Department or by      |
| one of the buyers.  A contributing cause to this loss was failure of the     |
| Surplus Property Staff to notify the UW Radiation Safety Office of the       |
| auction.  UW Radiation Safety routinely conducts "walk-through"              |
| inspections prior to auctions and as worked with Surplus Property Staff      |
| to help them identify hazardous equipment.  There was no explanation why     |
| the Radiation Safety Office had been removed from the auction                |
| announcement database.  This was corrected.  There is little likelihood      |
| of human exposure to the radioactive source if it was sent to the            |
| landfill for disposal with the other trash.                                  |
|                                                                              |
| What is the notification or reporting criteria involved? WAC                 |
| 246-221-240(1)(b) Reporting the loss of radioactive material in a            |
| quantity requiring notification within 30 days of occurrence.                |
|                                                                              |
| Activity and Isotope(s) involved: 15 millicuries of Ni-63 as of November     |
| 1, 1997                                                                      |
|                                                                              |
| Lost, Stolen or Damaged? (Mfg., Model, serial number) Perkins-Elmer gas      |
| chromatograph source model B3C0119, serial number 3512.                      |
| Leak test?  Source was last leak tested on September 19, 1998.  No           |
| indication of leakage.                                                       |
| Disposition/recovery: Source is believed to have been discarded into the     |
| trash sent to a landfill.                                                    |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Fuel Cycle Facility                              |Event Number:   35768       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: PORTSMOUTH GASEOUS DIFFUSION PLANT   |NOTIFICATION DATE: 05/26/1999|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 04:29[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        05/25/1999|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        21:05[EDT]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  05/26/1999|
|    CITY:  PIKETON                  REGION:  3  +-----------------------------+
|  COUNTY:  PIKE                      STATE:  OH |PERSON          ORGANIZATION |
|LICENSE#:  GDP-2                 AGREEMENT:  N  |TONY VEGEL           R3      |
|  DOCKET:  0707002                              |                     NMSS    |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  RON CRABTREE                 |                             |
|  HQ OPS OFFICER:  STEVE SANDIN                 |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NBNL                     RESPONSE-BULLETIN      |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| 24-HOUR NRC BULLETIN 91-01 REPORT INVOLVING THE LOSS OF ONE OF THE TWO       |
| DOUBLE CONTINGENCY CONTROLS                                                  |
|                                                                              |
| "On 5/25/99 at 2105 hours, while processing waste water solution through     |
| X-705 microfiltration filter press 'A', approximately 5 gallons of solution  |
| leaked from between the second and third filter plates, spilling onto the    |
| floor. At the time of this spill, Operations personnel were processing a     |
| 2072 liter 'batch' of waste water which contained 29.44 grams of U-235 at an |
| enrichment of 1.4 wt %  U-235.  Plant Nuclear Criticality Safety Personnel   |
| determined the leak to be a loss of a single control (physical integrity of  |
| the system) such that only one of the double contingency controls (geometry) |
| remained in place.                                                           |
|                                                                              |
| "This event is reportable under NRC Bulletin 91-01, 24-hour criticality      |
| control.                                                                     |
|                                                                              |
| "There was no radioactive / radiological exposure as a result of this        |
| event.                                                                       |
|                                                                              |
| "SAFETY SIGNIFICANCE OF EVENTS:                                              |
| On May 25, 1999, approximately 5-gallons of concentrate leaked from filter   |
| press A in the microfiltration system. The leak occurred between the second  |
| and third filter press plates, most likely the result of a failed 0-ring.    |
| NCSA.0705_076 covers the use of inadvertent containers in X-705, given the   |
| concern of leaks/spills from the various solution bearing systems.           |
| NCSA.0705_076 considers the leak/spill of more than 4.8-liters from any      |
| system to be an unlikely event, given the design and physical integrity of   |
| the systems (i.e., the systems are designed and built to contain the         |
| solution). While this leak resulted in greater than 4.8-liters spilling from |
| the system in question, the second contingency was not violated in that the  |
| solution did not accumulate in an unsafe geometry (it spilled to the floor   |
| and spread out into a safe slab geometry).                                   |
|                                                                              |
| "Based on sampling and batching calculations performed on the concentrate    |
| storage tank (i.e., T.103A) the total mass of material to be fed to the      |
| filter press is known prior to introducing concentrate into the filler       |
| press. NCSA-0705_015 limits the mass of U-235 to be processed (i.e., in a    |
| single batch) to a maximum of 350 grams. Per the filter press batch sheet    |
| for batch 103A-511, the batch being fed when this leak occurred contained    |
| 29.44 grams U-235. This amount of material is well below the safe mass of    |
| material, even at 100 wt% enrichment (ref. GAT-225). The actual enrichment   |
| of the material being processed was 1.4% U-235, per the filter press batch   |
| sheet for batch 103A-511. Therefore, while one of the contingencies was      |
| lost, the safety significance for this occurrence was low given the          |
| prerequisite for limiting the mass in the batch to 350 grams U-235.          |
|                                                                              |
| "POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO[S] OF HOW           |
| CRITICALITY COULD OCCUR):                                                    |
| A significant amount of uranium-bearing solution would have to leak from a   |
| system and accumulate in an unsafe geometry in order for a criticality to    |
| occur.                                                                       |
|                                                                              |
| "CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.):    |
| The parameters being controlled for this event were volume of a leak in a    |
| system in X-705. NCSA-0705_076 considers it unlikely that a leak of more     |
| than 4.8-liters would occur given the physical integrity of systems in       |
| X-705. In addition, the mass of U-235 in the batch being processed was       |
| limited to a maximum of 350 grams.                                           |
|                                                                              |
| "ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL (INCLUDE PROCESS    |
| LIMIT AND % WORST CASE OF CRITICAL MASS):                                    |
| Based on PR-PST-99-02948 and filter press batch sheet for batch  103A-511    |
| the volume of solution which leaked was approximately 5-gallons. The maximum |
| amount of U-235 in the concentrate was 29.44 grams and the maximum           |
| enrichment of material was 1.4 wt% U-235. It should be noted that the actual |
| mass of U-235 which was in the leaked solution would be less than 29.44      |
| grams, since the total amount of solution being processed was 2072 liters.   |
|                                                                              |
| "NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION  |
| OF THE FAILURES OR DEFICIENCIES:                                             |
| NCSA-0705_075 considers it unlikely that more than 4.8-liters of solution    |
| would leak from a system given the physical integrity of the systems used in |
| X-705. The leak in question resulted in approximately 5-gallons of solution  |
| leaking from the filter press. This amount of solution exceeded the          |
| considered limit for the unlikely event and resulted in the loss of double   |
| contingency for this leak.                                                   |
|                                                                              |
| "CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEM AND WHEN EACH WAS               |
| IMPLEMENTED:"                                                                |
|                                                                              |
| Operations informed the NRC resident inspector and will inform the DOE site  |
| representative.                                                              |
+------------------------------------------------------------------------------+


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