ML23268A319
| ML23268A319 | |
| Person / Time | |
|---|---|
| Site: | 07003103 |
| Issue date: | 09/25/2023 |
| From: | Louisiana Energy Services, URENCO USA |
| To: | Office of Nuclear Material Safety and Safeguards |
| Shared Package | |
| ML23268A317 | List: |
| References | |
| LES-23-138-NRC | |
| Download: ML23268A319 (1) | |
Text
LES-23-138-NRC Enclosure 1 60 Day Report for EN 56670, Waste Container Stacking Not Analyzed 10 CFR 70.50(c)(1)
(i) Caller's name, position title, and call-back telephone number;
- The individual who facilitated Event Notification 56670 was Jim Rickman, Senior Licensing Specialist. The call-back telephone number is 575-394-6558.
(ii) Date, time, and exact location of the event;
- The event occurred at 1422 MT on August 8, 2023. The location of this event was at Urenco USA in Eunice, New Mexico (Lea County).
(iii) Description of the event; CSA containers are temporarily stored in isolation (60cm spacing) in the rooms of the CRDB where IROFS58a/b are applicable. On August 8, 2023, an engineer identified an apparent condition in which there was no analysis of dropping one CSA container on another, in this storage arrangement. As a result, Urenco USA reported this event IAW 10 CFR 70 Appendix A, paragraph (b)(1).
(A) Radiological or chemical hazards involved, including isotopes, quantities, and chemical and physical form of any material released;
- There were no radiological or chemical hazards involved or released.
(B) Actual or potential health and safety consequences to the workers, the public, and the environment, including relevant chemical and radiation data for actual personnel exposures to radiation or radioactive materials or hazardous chemicals produced from licensed materials (e.g., level of radiation exposure, concentration of chemicals, and duration of exposure);
- There were no actual or potential health and safety consequences to workers, the public, or the environment. No unexpected exposure to radioactive materials or hazardous chemicals produced from licensed materials occurred.
- Plant instrumentation detected no release during the event.
- No contamination events occurred; therefore, no decontamination was necessary.
- No dose alarms or dose rate alarms occurred during the response.
Urenco USA UUSA l P.O. Box 1789 l 275 Hwy. 176 l Eunice l New Mexico l 88231 l USA T: +1 (575) 394-4646 l W: www.urencousa.com
© 2023 Urenco USA Inc.
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LES-23-138-NRC (C) The sequence of occurrences leading to the event, including degradation or failure of structures, systems, equipment, components, and activities of personnel relied on to prevent potential accidents or mitigate their consequences; and
- On 8/8/2023, a UUSA engineer determined that although CSA containers in the stacked engineered array were evaluated in NCS-CSA-022, the engineer believed that the scenario of dropping a CSA container on an isolated CSA container (i.e. not stored in an engineered array) should also be explicitly described within NCS-CSA-022. As a result, EV 161478 was written.
- On 8/9/2023, Urenco USA determined that EV 161478 was reportable per 10 CFR 70 Appendix A paragraph (b)(1)
(D) Whether the remaining structures, systems, equipment, components, and activities of personnel relied on to prevent potential accidents or mitigate their consequences are available and reliable to perform their function;
- Placing of CSA containers containing enriched material is controlled by limiting the mass (IROFS58a) and maintaining spacing (IROFS58b) when containers are placed in an array. In this case, containers were not placed in an array and there is no indication that IROFS58a and IROFS58b would not perform their safety function.
- UUSA stopped work involving the movement of CSA containers in the rooms of the CRDB where IROFS58a/b are applicable.
(iv) External conditions affecting the event;
- There were no external conditions affecting this event.
(v) Additional actions taken by the licensee in response to the event;
- Work involving the movement of CSA containers in the CRDB rooms of the CRDB where IROFS58a/b are applicable, was stopped.
- The event was entered into the Corrective Action Program as EV161478 on 8/08/2023.
- The event was investigated and the cause determined to be a misunderstanding of the analysis
- Plans are in place to better document the analysis of stacked, isolated cylinders.
Urenco USA UUSA l P.O. Box 1789 l 275 Hwy. 176 l Eunice l New Mexico l 88231 l USA T: +1 (575) 394-4646 l W: www.urencousa.com
© 2023 Urenco USA Inc.
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LES-23-138-NRC (vi) Status of the event (e.g., whether the event is on-going or was terminated);
- The event has been terminated.
(vii) Current and planned site status, including any declared emergency class;
- The site is functional for uranium enrichment.
- Work involving movement of CSA containers in the rooms of the CRDB where IROFS58a/b are applicable remains stopped.
- React action AC 176094 will revise the associated Nuclear Criticality Safety Analysis (viii) Notifications, related to the event, that were made or are planned to any local, State, or other Federal agencies;
- The NRC was notified on 8/9/2023. No other notifications were made or are planned to other government agencies.
(ix) Status of any press releases, related to the event, that were made or are planned.
- No press releases were made and no press releases are planned.
(ii) The probable cause of the event, including all factors that contributed to the event and the manufacturer and model number (if applicable) of any equipment that failed or malfunctioned;
- The cause of this event was determined to be the lack of clarity in the analysis. The analysis of a dropped CSA container onto an isolated container is bounded by NCS-CSA-022 but was not written as the engineer expected. This resulted in the engineer assuming that the particular scenario was not included in the analysis.
(iii) Corrective actions taken or planned to prevent occurrence of similar or identical events in the future and the results of any evaluations or assessments;
- Urenco USA has initiated React action AC 176094 to revise NCS-CSA-022 to clarify the analysis of spacing upsets regarding one container on top of another, as well as a lateral upset for isolated containers.
(iv) For licensees subject to Subpart H of this part, whether the event was identified and evaluated in the Integrated Safety Analysis.
Urenco USA has concluded that two stacked containers that are isolated from other containers, is an analyzed condition. The safety analysis documentation does not clearly state this and will be revised to clarify.
Urenco USA UUSA l P.O. Box 1789 l 275 Hwy. 176 l Eunice l New Mexico l 88231 l USA T: +1 (575) 394-4646 l W: www.urencousa.com
© 2023 Urenco USA Inc.
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