Event Notification Report for June 2, 2000
U.S. Nuclear Regulatory Commission
Operations Center
Event Reports For
06/01/2000 - 06/02/2000
** EVENT NUMBERS **
37046 37047
!!!!!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED !!!!!!!
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|Power Reactor |Event Number: 37046 |
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| FACILITY: LASALLE REGION: 3 |NOTIFICATION DATE: 05/31/2000|
| UNIT: [] [2] [] STATE: IL |NOTIFICATION TIME: 18:04[EDT]|
| RXTYPE: [1] GE-5,[2] GE-5 |EVENT DATE: 05/31/2000|
+------------------------------------------------+EVENT TIME: 13:30[CDT]|
| NRC NOTIFIED BY: COVEYOU |LAST UPDATE DATE: 06/02/2000|
| HQ OPS OFFICER: CHAUNCEY GOULD +-----------------------------+
+------------------------------------------------+PERSON ORGANIZATION |
|EMERGENCY CLASS: N/A |GARY SHEAR R3 |
|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 97 Power Operation |97 Power Operation |
| | |
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EVENT TEXT
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| PLANT ENTERED A 7 DAY LCO DUE TO HPCS BEING DECLARED INOPERABLE. |
| |
| While performing monthly surveillance start LOS-DG-M3, for the High-Pressure |
| Core Spray (HPCS) systems Emergency Diesel Generator, the Diesel |
| automatically tripped off on an over-speed signal. The Diesel was being |
| started from an idle condition while an operator was attempting to maintain |
| speed between 400 and 500 rpm. The Diesel does not appear to have been |
| damaged but remains shutdown and unavailable for on-going investigation of |
| the failure. The High-Pressure Core Spray system is inoperable but available |
| from normal power source only. The failure mechanism is being investigated |
| and corrective actions will be performed. |
| |
| The NRC Resident Inspector was notified. |
| |
| * * * UPDATE AT 2211 ON 06/01/00 BY SHANE MARIK TO JOLLIFFE * * * |
| |
| |
| The licensee investigation has determined that the cause of the event was |
| due to operator overcompensation of the engine governor during the start |
| that resulted in the EDG accelerating to the overspeed setpoint and tripping |
| on overspeed. The operator performing the slow (idle) start in accordance |
| with the monthly Technical |
| Specification surveillance procedure was a trainee under supervision by a |
| qualified operator. The EDG was already inoperable for the performance of |
| the monthly surveillance test that verifies operability of the EDG to start |
| and carry full load for at least 60 minutes. During inspection, no |
| mechanical or electrical malfunctions were |
| found associated with governor settings, the start circuitry, the engine |
| fuel racks, or fuel injector linkages. The fuel rack and associated fuel |
| injector linkages were then verified to have freedom of movement without |
| binding. A subsequent fast start was performed (same as an automatic start) |
| that verified that the EDG did not have a malfunction that would cause it to |
| trip on overspeed. The EDG would have satisfied its intended safety |
| function when in standby (no operator interface is required for the |
| governor/fuel rack control. except for surveillance testing). Therefore, |
| the overspeed trip of the High Pressure Core Spray System EDG is not |
| reportable as a |
| condition that alone could have prevented fulfillment of a safety function. |
| |
| Since the failure occurred after the EDG was inoperable due to not being |
| lined up for standby operation (removed from service as part of a planned |
| evolution in accordance with an approved procedure), the start was a slow |
| start controlled by an operator and restoration of the EDG was less than 12 |
| hours and well within the 14 day Technical Specification allowed outage |
| time. The licensee has determined that this event is not reportable to the |
| NRC, and desires to retract this event notification. |
| |
| The licensee notified the NRC Resident Inspector. |
| |
| The NRC Operations Officer notified the R3DO Bruce Jorgensen. |
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|Fuel Cycle Facility |Event Number: 37047 |
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| FACILITY: PORTSMOUTH GASEOUS DIFFUSION PLANT |NOTIFICATION DATE: 06/01/2000|
| RXTYPE: URANIUM ENRICHMENT FACILITY |NOTIFICATION TIME: 09:34[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER |EVENT DATE: 05/31/2000|
| 6903 ROCKLEDGE DRIVE |EVENT TIME: 10:00[EDT]|
| BETHESDA, MD 20817 (301)564-3200 |LAST UPDATE DATE: 06/01/2000|
| CITY: PIKETON REGION: 3 +-----------------------------+
| COUNTY: PIKE STATE: OH |PERSON ORGANIZATION |
|LICENSE#: GDP-2 AGREEMENT: N |GARY SHEAR R3 |
| DOCKET: 0707002 |BRIAN SMITH NMSS |
+------------------------------------------------+ |
| NRC NOTIFIED BY: JEFF CASTLE | |
| 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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| CATEGORY 1 AND CATEGORY 2 MATERIAL FOUND WITHIN 2 FEET OF EACH OTHER |
| |
| NRC Bulletin 91-01 24 hour notification |
| |
| On May 31, 2000, PORTS plant personnel discovered NCSA-PLANT048 |
| non-compliance during the monthly Nuclear Criticality Safety (NCS) walk |
| through. Category 1 contaminated metal was discovered in close proximity |
| (less than 2 feet) to Category 2 contaminated metal. Category 1 contaminated |
| metal is defined as items that have no visible uranium on them, items only |
| contaminated with non-fissile radiological isotopes, items from a |
| non-fissile material operation or items with hidden cavities from |
| non-fissile material operations. Category 2 contaminated metal is defined as |
| an item that has a hidden cavity with potential for significant uranium |
| material in the cavity. This was a violation of NCSA-PLANT048 requirement # |
| 2 which states, "Category 2 contaminated metal shall not be stored in a |
| Category 1 contaminated metal storage area". This constituted the loss of |
| one control (spacing) of the double contingency principle. The first control |
| (that of not storing Category 2 Items with Category 1) was lost. The second |
| control (that of categorizing the Category 1 metal Items correctly, mass |
| control) was maintained throughout this event. This condition was corrected |
| under NCS Engineering guidance and compliance re-established at 1205 hours. |
| |
| The monthly NCS walk through also identified a NCSA-PLANT048 administrative |
| noncompliance. NCSA-PLANT048 "Contaminated Metal" requires that a sign be |
| posted for Category 2 contaminated metal storage areas. The converters |
| stored outside of the X-700 building meet the requirements of Category 2 |
| contaminated metal but the area was not posted. Temporary signs were posted |
| to re-establish compliance with NCSA-PLANT048. |
| |
| SAFETY SIGNIFICANCE OF EVENTS: |
| |
| This event has low safety significance. The six converters on the west side |
| of X-700 contain less than a safe mass at the indicated enrichment. There |
| were no visible uranium compounds on the Category 1 contaminated metal that |
| was stored In close proximity to the converters. Since there was no visible |
| uranium on the Category 1 metal, there was no additional risk of a |
| criticality occurring. NCSE-PLANT048.E04 documents that Category 1 |
| contaminated metal can have at most 24.2 grams 235U per 2,500 square feet of |
| metal surface. In no case was more than 2500 square feet of Category 1 |
| material found within 2 feet of the six converters. |
| |
| NDA results indicate (with uncertainty applied) that the largest amount of |
| 235U in one converter is 1099 grams at an enrichment of 2.3 wt% 235U in the |
| form of UO2F2. At 3 wt% 235U, the estimated minimum critical mass is 3,077 |
| grams 235U and the safe mass is 1180 grams of 235U. Assuming 25 additional |
| grams of 235U due to the presence of the Category 1 metal, the total amount |
| of 235U (1124 grams 235U) is still below a safe mass, for the converter unit |
| with the highest loading. |
| |
| POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO[S] OF HOW |
| CRITICALITY COULD OCCUR): |
| |
| A 'dirty' metal item classified as Category 1 with the 'dirt' containing a |
| large amount of enriched uranium stored with a Category 2 item such that the |
| total uranium present exceeds a critical mass and is in the proper geometry |
| for a criticality to occur |
| |
| CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.): |
| |
| The controlled parameters are the segregation (proper spacing) of Category 1 |
| and 2 storage areas and the proper classification of the Category 1 |
| contaminated metal items (mass control). |
| |
| ESTIMATED AMOUNT, ENRICHMENT. FORM OF LICENSED MATERIAL (INCLUDE PROCESS |
| LIMIT AND % WORST CASE OF CRITICAL MASS): |
| |
| NDA results indicate (with uncertainty applied) that the largest amount of |
| 235U in one converter is 1099 grams at an enrichment of 2.3 wt% 235U in the |
| form of UO2F2. At 3 wt% 235U, the estimated minimum critical mass is 3,077 |
| grams 235U due to the presence of the Category 1 metal, the total amount of |
| 235U (1124 grams 235U) is still below a safe mass, for the converter unit |
| with the highest loading. |
| |
| NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION |
| OF THE FAILURES OR DEFICIENCIES: |
| |
| The first control that of not storing Category 2 items with Category 1 Items |
| (spacing) was lost. The second control, that of categorizing the Category 1 |
| metal items was done correctly (mass control). The Category 1 items were |
| observed to have no visible uranium on them. Thus, the first control was |
| lost but the second control of categorizing the Category 1 contaminated |
| metal items was done correctly. This resulted in a lost on one control |
| (spacing) relied on for double contingency. |
| |
| CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEM AND WHEN EACH WAS IMPLEMENTED: |
| |
| At 1205 hours, under NCS engineering guidance, the Category 1 contaminated |
| metal was spaced at least 2 feet from all Category 2 contaminated metal |
| (converters). Signs were posted identifying the Category 2 contaminated |
| metal storage area. |
| |
| The NRC Resident Inspector was notified of this event by the certificate |
| holder. |
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Page Last Reviewed/Updated Wednesday, March 24, 2021
Page Last Reviewed/Updated Wednesday, March 24, 2021