Event Notification Report for February 14, 2003
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
02/13/2003 - 02/14/2003
Fuel Cycle Facility
Event Number: 39588
Facility: PADUCAH GASEOUS DIFFUSION PLANT
Region: 3 State: KY
Unit: [] [] []
RX Type: URANIUM ENRICHMENT FACILITY
Comments: 2 DEMOCRACY CENTER
6903 ROCKLEDGE DRIVE
BETHESDA, MD 20817 (301)564-3200
NRC Notified By: STEVEN SKAGGS
HQ OPS Officer: HOWIE CROUCH
Region: 3 State: KY
Unit: [] [] []
RX Type: URANIUM ENRICHMENT FACILITY
Comments: 2 DEMOCRACY CENTER
6903 ROCKLEDGE DRIVE
BETHESDA, MD 20817 (301)564-3200
NRC Notified By: STEVEN SKAGGS
HQ OPS Officer: HOWIE CROUCH
Notification Date: 02/15/2003
Notification Time: 16:15 [ET]
Event Date: 02/14/2003
Event Time: 19:00 [CST]
Last Update Date: 02/15/2003
Notification Time: 16:15 [ET]
Event Date: 02/14/2003
Event Time: 19:00 [CST]
Last Update Date: 02/15/2003
Emergency Class: NON EMERGENCY
10 CFR Section:
10 CFR Section:
Person (Organization):
SONIA BURGESS (R3)
PATRICIA HOLAHAN (NMSS)
SONIA BURGESS (R3)
PATRICIA HOLAHAN (NMSS)
CRITICALITY CONTROL 24-HOUR (BULLETIN 91-01) REPORT
The following information was obtained from the regulatee via facsimile:
"At 1900 on 2-14-03, the Plant Shift Superintendent (PSS) was notified that the C-333 "E" Surge Drum, 0-25 psia pressure recorder was not working and the 0-2 pressure recorder was off-scale. The 0-25 psia pressure recorder had failed violating the requirements of a Safety Related Item (SRI) credited in NCSE [Nuclear Criticality Safety Evaluation] 016. As a result, the shiftly pressure checks could not be performed. Instead of installing a sample buggy to measure pressure, the drum pressure was reduced in order to read the pressure on the 0-2 [psia] pressure chart recorder. The purpose of the pressure check is to identify if wet air in-leakage has begun on the surge drum bank.
"Double contingency has been restored since the ability to read pressure in the surge drum bank using a properly operating AQ-NCS [Augmented Quality - Nuclear Criticality Safety] pressure instrument has been restored.
"The NRC Resident Inspector has been notified of this event.
"SAFETY SIGNIFICANCE OF EVENTS:
"Although pressure readings could not be taken due to a failed AQ-NCS pressure instrument, there are several important mitigating factors. First, the integrity of the drum bank has been maintained. Second, the uranium has been maintained in the gas phase.
"POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO(S) OF HOW CRITICALITY COULD OCCUR)
"These drums are used to store gasses. Therefore, in order for a criticality to be possible, wet air would have to react with any UF6 in the drum. The leak would have to occur over a long period, in order to create a large mass of U02F2 and then sufficiently moderate the material.
"CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.)
"Double contingency is maintained by implementation of two controls on moderation.
"ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL(INCLUDE PROCESS LIMIT AND % WORST CASE CRITICAL MASS);
"The material in the Surge Drum is in a gaseous state. System NCS limit is 1.7 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 maintaining the integrity of the surge drum system against wet air in leakage. This integrity is assured by a SRI for the unlikely breach of the surge drum system. Structural integrity of the drum is intact, therefore this SRI is maintained.
"The second leg of double contingency is based on the performance of shiftly pressure checks using an AQ-NCS instrument as an indication of wet air in-leakage. The required checks could not be performed due to a failed instrument, resulting in a loss of this control. Instead of installing a sample buggy to measure pressure, the drum pressure was reduced in order to read the pressure on the 0-2 pressure chart recorder. Since there are two controls on one parameter, double contingency was not maintained.
"Even though moderation control was maintained, double contingency is based on two controls on moderation. Therefore, double contingency was not maintained.
"CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED:
None."
The following information was obtained from the regulatee via facsimile:
"At 1900 on 2-14-03, the Plant Shift Superintendent (PSS) was notified that the C-333 "E" Surge Drum, 0-25 psia pressure recorder was not working and the 0-2 pressure recorder was off-scale. The 0-25 psia pressure recorder had failed violating the requirements of a Safety Related Item (SRI) credited in NCSE [Nuclear Criticality Safety Evaluation] 016. As a result, the shiftly pressure checks could not be performed. Instead of installing a sample buggy to measure pressure, the drum pressure was reduced in order to read the pressure on the 0-2 [psia] pressure chart recorder. The purpose of the pressure check is to identify if wet air in-leakage has begun on the surge drum bank.
"Double contingency has been restored since the ability to read pressure in the surge drum bank using a properly operating AQ-NCS [Augmented Quality - Nuclear Criticality Safety] pressure instrument has been restored.
"The NRC Resident Inspector has been notified of this event.
"SAFETY SIGNIFICANCE OF EVENTS:
"Although pressure readings could not be taken due to a failed AQ-NCS pressure instrument, there are several important mitigating factors. First, the integrity of the drum bank has been maintained. Second, the uranium has been maintained in the gas phase.
"POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO(S) OF HOW CRITICALITY COULD OCCUR)
"These drums are used to store gasses. Therefore, in order for a criticality to be possible, wet air would have to react with any UF6 in the drum. The leak would have to occur over a long period, in order to create a large mass of U02F2 and then sufficiently moderate the material.
"CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.)
"Double contingency is maintained by implementation of two controls on moderation.
"ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL(INCLUDE PROCESS LIMIT AND % WORST CASE CRITICAL MASS);
"The material in the Surge Drum is in a gaseous state. System NCS limit is 1.7 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 maintaining the integrity of the surge drum system against wet air in leakage. This integrity is assured by a SRI for the unlikely breach of the surge drum system. Structural integrity of the drum is intact, therefore this SRI is maintained.
"The second leg of double contingency is based on the performance of shiftly pressure checks using an AQ-NCS instrument as an indication of wet air in-leakage. The required checks could not be performed due to a failed instrument, resulting in a loss of this control. Instead of installing a sample buggy to measure pressure, the drum pressure was reduced in order to read the pressure on the 0-2 pressure chart recorder. Since there are two controls on one parameter, double contingency was not maintained.
"Even though moderation control was maintained, double contingency is based on two controls on moderation. Therefore, double contingency was not maintained.
"CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED:
None."
General Information or Other
Event Number: 39642
Rep Org: LOUISIANA DEPT ENV QUALITY
Licensee: HALIBURTON
Region: 4
City: State: LA
County:
License #: LA-2353-L01
Agreement: Y
Docket:
NRC Notified By: SCOTT BLACKWELL
HQ OPS Officer: YAMIR DIAZ
Licensee: HALIBURTON
Region: 4
City: State: LA
County:
License #: LA-2353-L01
Agreement: Y
Docket:
NRC Notified By: SCOTT BLACKWELL
HQ OPS Officer: YAMIR DIAZ
Notification Date: 03/06/2003
Notification Time: 15:31 [ET]
Event Date: 02/14/2003
Event Time: 00:00 [CST]
Last Update Date: 03/06/2003
Notification Time: 15:31 [ET]
Event Date: 02/14/2003
Event Time: 00:00 [CST]
Last Update Date: 03/06/2003
Emergency Class: NON EMERGENCY
10 CFR Section:
10 CFR Section:
Person (Organization):
DALE POWERS (R4)
DOUG BROADDUS (NMSS)
DALE POWERS (R4)
DOUG BROADDUS (NMSS)
IRRETRIEVABLE SEALED SOURCE
"An NWA tool with a 2 Ci [Curie] source of Cs-137 and a 4 Ci source of Am241Be were lost down [a] hole at 11540 feet on February 14, 2003. Attempts were made until February 20, 2003 to retrieve the tool, but they were unsuccessful. The well was back filled with 500 ft of cement to a depth of 10881 ft. DEQ is currently waiting for the written report for additional information."
"An NWA tool with a 2 Ci [Curie] source of Cs-137 and a 4 Ci source of Am241Be were lost down [a] hole at 11540 feet on February 14, 2003. Attempts were made until February 20, 2003 to retrieve the tool, but they were unsuccessful. The well was back filled with 500 ft of cement to a depth of 10881 ft. DEQ is currently waiting for the written report for additional information."