ENS 50577
ENS Event | |
|---|---|
07:00 Oct 29, 2014 | |
| Title | Unanalyzed Condition Due to Material in a Thermocouple Housing |
| Event Description | While performing troubleshooting on a thermocouple, uranium-bearing material was found inside the sealed housing containing the wiring block for the thermocouple. A very small amount (less than one ounce) of wet paste-like material was removed from the housing for analysis. The leak appears to be low concentration material that has penetrated the enclosed thermocouple well. The material was contained within the housing; however, the electrical conduit exiting the housing connects to an electrical panel that is an unfavorable geometry.
Potential health and safety consequences: "No actual safety consequences occurred due to this event. The potential consequences would result if a sufficient volume of HEU solution were to leak through the thermocouple well and drain through the electrical conduit into an unfavorable geometry electrical panel, which could under worst case conditions lead to a criticality accident. The leaked material was contained within the instrument housing and no personnel exposures resulted. Sequence of occurrences leading to the event: "The integrity of a thermocouple well failed allowing a very small quantity of low concentration material to enter the housing containing the thermocouple connections. The leak was identified during troubleshooting operational issues with the system. At this point, the failure mechanism of the thermocouple well is unknown. Additional actions taken in response to the event: Similar systems are being inspected to determine if additional failures are present. Also, corrective actions to include modification of the unfavorable geometry electrical panels that have not been previously modified are underway to eliminate this failure pathway. What is the safety significance of the event? Low safety significance due to limited quantity as well as geometry of container. The licensee has notified the NRC Resident Inspector. |
| Where | |
|---|---|
| Nuclear Fuel Services Inc. Erwin, Tennessee (NRC Region 2) | |
| License number: | SNM-124 |
| Reporting | |
| Part 70 App A (B)(1) | |
| Time - Person (Reporting Time:+10.53 h0.439 days <br />0.0627 weeks <br />0.0144 months <br />) | |
| Opened: | Randy Shackelford 17:32 Oct 29, 2014 |
| NRC Officer: | Howie Crouch |
| Last Updated: | Oct 29, 2014 |
| 50577 - NRC Website | |
Nuclear Fuel Services Inc. with Part 70 App A (B)(1) | |
WEEKMONTHYEARENS 505772014-10-29T07:00:00029 October 2014 07:00:00
[Table view]Part 70 App A (B)(1) Unanalyzed Condition Due to Material in a Thermocouple Housing ENS 462842010-09-27T17:41:00027 September 2010 17:41:00 Part 70 App A (B)(1) Unusual Buildup of Material in Aluminum Centrifuge Area ENS 454462009-10-13T04:00:00013 October 2009 04:00:00 Part 70 App A (B)(1) Nitrous Oxide (Nox) Generation Rate Higher than Expected After Aluminum Fines Were Introduced ENS 439372008-01-15T21:21:00015 January 2008 21:21:00 Part 70 App A (B)(1) Inadequate Inspections on Thru-Wall Piping Penetration Sleeves ENS 416512005-04-28T21:30:00028 April 2005 21:30:00 Part 70 App A (B)(1)
2014-10-29T07:00:00 | |