ENS 40109
ENS Event | |
|---|---|
14:00 Aug 27, 2003 | |
| Title | Procedural Deficiency Omission |
| Event Description | NRC BULLETIN 91-01 24 HOUR NOTIFICATION
At 0900 on 8/27/03, it was discovered that the procedure for operation of the C-409 Uranium Precipitation System did not adequately address flowdown requirements specified in NCSA 409-001. NCSA 409-001 control 3.2.39 prevents introduction of organic material to the precipitation system by requiring verification that the solution originated from either the C-710 Laboratory, the C-409 Cylinder Wash, or the C-409 Uranium Precipitation System and that the solution does not contain organic material, as indicated by sampling. The control had been flowed down for solutions originating from the C-710 Laboratory and the C-409 Cylinder Wash, however was not flowed down for solutions originating from the C-409 Uranium Precipitating System. PGDP Assessment and Tracking Report No. ATR 03-2767, PGDP Event Report No. PAD-2003-017. SAFETY SIGNIFICANCE OF EVENTS: Double contingency was not maintained because the independent verification of the origination of solutions from the C-409 Uranium Precipitation System and the independent verification that the solution did not contain organic material had not been performed. However, no oil has been introduced to the operation. POTENTIAL CRITICALITY PATHWAYS INVOLVED OF HOW CRITICALITY COULD OCCUR: In order for a criticality to be possible, greater than a safe mass of uranium must be accumulated within the Uranium Precipitation System, facilitated by the presence of organic material and accumulate in the rotary drum filter. CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.) Double contingency is maintained by implementing two controls on mass. ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL: This system has a process limit of (xx) wt.% U235. NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION OF THE FAILURES OF DEFICIENCIES: The first leg of double contingency is based on controlling the mass of uranium in the tanks. NCSA 409-001 requires that prior to placing solution in the Uranium Precipitation Operation the solution must be verified to be uranium salvage from C-710 laboratory, C-409 cylinder wash, or the C-409 Uranium Precipitation System and that the solution does not contain organic material. This control prevents the build-up of organic material at the top of the Uranium Precipitation System tanks. If organic material were to get in the tanks it would create a floating uranium/oil layer and result in non-representative sampling of the concentration, since sampling is conducted near the bottom of the tank. This may lead to an unsafe mass reaching the rotary drum filter. The C-710 solution currently in the system was independently verified to be free of organic material prior to initial introduction. However, since no verification was documented for the C-409 Uranium Precipitation system solution, this control was lost. Chemical Operations personnel have subsequently verified that no events have occurred to introduce organic material into the solution from the C-409 Uranium Precipitation System. The control was violated; however the parameter was maintained. The second leg of double contingency is based on mass. NCSA 409-001 requires that prior to placing solution in the Uranium Precipitation Operation, the solution be independently verified to be uranium salvage from C-710 Laboratory, C-409 Cylinder Wash or the C-409 Uranium Precipitation System and that the solution does not contain organic material. However, since no independent verification was documented for the C-409 Uranium Precipitation system solution, this control was lost. Chemical Operations personnel have subsequently independently verified that no events have occurred to introduce organic material into the solution from the C-409 Uranium Precipitation System. Therefore, this control was violated. Since there are two controls on one parameter, double contingency was not maintained. Since double contingency is based on two controls on one parameter, and the controls were violated, double contingency was not maintained. CORRECTIVE ACTIONS TO REESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED: Chemical Operations revise procedure CP4-CU-CH2137 to include verification requirements specified in NCSA 409-001. Procedure change was initiated on 8-27-03. The NRC Senior Resident Inspector has been notified of this event by the licensee. |
| Where | |
|---|---|
| Paducah Gaseous Diffusion Plant Paducah, Kentucky (NRC Region 3) | |
| License number: | GDP-1 |
| Reporting | |
| Response | |
| Time - Person (Reporting Time:+13.88 h0.578 days <br />0.0826 weeks <br />0.019 months <br />) | |
| Opened: | Steven Shaggs 03:53 Aug 28, 2003 |
| NRC Officer: | John Mackinnon |
| Last Updated: | Aug 27, 2003 |
| 40109 - NRC Website | |
Paducah Gaseous Diffusion Plant with Response | |
WEEKMONTHYEARENS 483982012-10-10T18:05:00010 October 2012 18:05:00
[Table view]Response Double Contingency Control for Empty Cylinders Not Maintained ENS 479112012-05-08T21:16:0008 May 2012 21:16:00 10 CFR 76.120(c)(2), Response Autoclave High Pressure Isolation System Failure ENS 474832011-11-28T15:30:00028 November 2011 15:30:00 Response 24-Hour Report Concerning a Localized Loss of a Geometry Criticality Control Contingency ENS 473102011-09-30T13:54:00030 September 2011 13:54:00 Response 24-Hour Nrc Bulletin 91-01 Report Involving a Loss of One Leg of Double Contingency ENS 471762011-08-19T13:15:00019 August 2011 13:15:00 Response 24-Hr Loss of Criticality Control Report Required Under Bulletin 91-01, Supplement 1 ENS 465922011-02-03T15:30:0003 February 2011 15:30:00 Response 24 Hour Notification Under Bulletin 91-01 Concerning Leakage of Moderating Liquid ENS 463122010-10-06T16:06:0006 October 2010 16:06:00 Response 24 Hour Notification Under Bulletin 91-01 Concerning Cooldown Verification of Uf6 Cylinders ENS 461052010-07-17T19:07:00017 July 2010 19:07:00 Response 24 Hour 91-01 Bulletin Report on Loss of One of Two Criticality Control Contingencies ENS 454922009-11-12T17:15:00012 November 2009 17:15:00 Response Violation of a Nuclear Criticality Safety Control ENS 450422009-05-04T10:07:0004 May 2009 10:07:00 Response 24 Hour 91-01 Bulletin Report on Loss of One of Two Criticality Control Contingencies ENS 445582008-10-09T20:37:0009 October 2008 20:37:00 Response 24-Hours Bulletin 91-01 Report Involving Failure to Visually Inspect Storage Cylinders ENS 442232008-05-18T22:21:00018 May 2008 22:21:00 Response Violation of a Nuclear Criticality Safety Approval - 24-Hour Report ENS 441512008-04-17T21:44:00017 April 2008 21:44:00 Response 24-Hour Nrc Bulletin 91-01 Report Involving an Excessively Large Container Found in a Fissile Control Area ENS 441002008-03-26T19:57:00026 March 2008 19:57:00 Response 24 Hour Report of Degraded Criticality Control ENS 440562008-03-11T19:57:00011 March 2008 19:57:00 Response Two Cylinders Identified with Weight Change Prior to Wash ENS 432322006-09-23T03:00:00023 September 2006 03:00:00 Response Reported Under Nrc Bulletin 91-01 24 Hour Notification ENS 421652005-11-22T18:05:00022 November 2005 18:05:00 Response Improper Criticality Spacing for Waste Drum ENS 411582004-10-29T14:45:00029 October 2004 14:45:00 Response Criticality Control Report ENS 410202004-09-04T18:45:0004 September 2004 18:45:00 Response Violation of Nuclear Criticality Safety Control in the Process Building ENS 408732004-07-14T18:00:00014 July 2004 18:00:00 Response Criticality Control 24-Hour (Bulletin 91-01) Report ENS 408602004-07-08T20:50:0008 July 2004 20:50:00 Response 24 Hour Nrc Bulletin 91-01 Loss of Criticality Control ENS 407232004-05-03T21:00:0003 May 2004 21:00:00 Response Criticality Control 24-Hour (Bulletin 91-01) Report ENS 407002004-04-23T13:45:00023 April 2004 13:45:00 Response Criticality Control 24-Hour (Bulletin 91-01) Report ENS 408052004-04-23T10:53:00023 April 2004 10:53:00 Response Paducah Gaseous Diffussion Plant - Response Bulletin 91-01 24 - Hour Report ENS 406412004-04-04T19:30:0004 April 2004 19:30:00 Response 24-Hour Nrc Bulletin 91-01 Loss of Criticality Control Notification ENS 404552004-01-16T21:27:00016 January 2004 21:27:00 Response 24 Hour Notification for Bulletin 91-01 Loss of Criticality Safety Controls Involving Waste Drum ENS 404472004-01-13T19:00:00013 January 2004 19:00:00 Response 24 Hour Notification for Bulletin 91-01 Loss of Criticality Safety Controls Involving Waste Drum ENS 403562003-11-25T09:45:00025 November 2003 09:45:00 Response 24 Hour Nrc Bulletin 91-01 Notification Regarding Loss of Double Contingency Protection ENS 401512003-09-11T13:45:00011 September 2003 13:45:00 Response Double Contingency Was Not Maintained for Non-Fissile Nams. ENS 401392003-09-07T12:50:0007 September 2003 12:50:00 Response Criticality Controls Degradation at Paducah ENS 401092003-08-27T14:00:00027 August 2003 14:00:00 Response Procedural Deficiency Omission 2012-05-08T21:16:00 | |