ENS 57191
ENS Event | |
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15:00 Jun 25, 2024 | |
Title | Technical Specification Reportable Occurrence |
Event Description | The following information was provided by the licensee via phone and email:
In accordance with Technical Specification (TS) 6.7.2.1, a report is required to be made within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> by telephone, confirmed by digital submission or fax to the NRC Operations Center if requested, and followed by a report in writing to the NRC, Document Control Desk, Washington, D.C. within 14 days that describes the circumstances associated with eight different specifications, one of which, (h), is abnormal and significant degradation in reactor fuel, cladding, or coolant boundary. At approximately 0900 MDT this morning, abnormal and significant degradation in reactor cladding was observed on fuel element 681E, an aluminum-clad element being inspected for removal from service. The degradation was in the form of an L-shaped hole, approximately 0.25 inches long in the upper section of the fuel element body approximately one inch from the top edge, where the upper aluminum pin and upper graphite section meet internally. It is unknown how long this damage has existed, as there is no visual record of any of this fuel since first inspected in 2003 at the VA Omaha TRIGA reactor before USGS took possession. At that point, it did not have this damage. According to the records, it was dropped during handling in 2003 when it was being unloaded from the shipping cask here at the GSTR [Geological Survey TRIGA Reactor], but no record of further inspection appears to exist. Therefore, this element may have been in the operating core for as long as 18 years in this condition, as USGS was first licensed to use it in 2006. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: No fission products were detected in the primary, pool, or on an air particulate detector. The damaged element remains in its storage location in the pool with no other mitigating measures planned in the near term.
The following is a summary of information provided by the licensee via phone and email: After continued fuel inspections, four additional damaged fuel elements were identified (Fuel Element 3007, Fuel Element 5952, Fuel Follower Control Rod 5767, and Fuel Follower Control Rod 5768). The damaged elements will be moved to dry storage and will not be considered for further use. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: Inspections are approximately one third complete. Notified NRR PM (Boyle), NPR Event Coordinator (Waugh), and USGS PM (Sutherland).
[The licensee has] additional elements to report, under license technical specification 6.7.2.1 (h): Fuel element 3361, stainless-steel clad: Substantial cladding damage, but not an apparent breach. It has a severe scratch approximately one eighth of an inch wide along most of the element, and two other substantial scratches. The top of the main scratch terminates in what appears to be a cracking pattern, though likely not fully through the cladding, as no fission product release was detected. The element also exhibits apparent rust on the triangular spacer, covering approximately 10 percent of the serial number face surface. It will not be used in the future. None of our inspection records show a history of any damage. It was in service prior to this inspection. This element was transferred to our facility after previous use at Michigan State University in 1989, also having been previously used at General Atomics in San Diego. Estimated manufacture [date] in 1964. Fuel element 7932, stainless-steel clad: Substantial cladding damage, but not an apparent breach. It has multiple deep scratches, disconnected at the ends, though running in parallel for lengths down a side of the element for nearly the entire length. [The element] gives the appearance of potential separation, but no fission product release was detected. It will not be used in the future unless thorough non-destructive evaluation concludes sufficient cladding integrity remains. None of our inspection records show a history of any damage. It was in service prior to this inspection. This element was purchased directly from General Atomics new in 1974. Fuel element 9473, stainless-steel clad: Multiple deep scratches on several sides with little to no light reflection. Scratches are typical on elements, however, the appear to threaten the integrity of the cladding and further use may result in release, though none has been detected yet. It will not be used in the future unless thorough non-destructive evaluation concludes sufficient cladding integrity remains. None of our inspection records show a history of any damage. It was in service prior to this inspection. This element was purchased directly from General Atomics new in 1980. Fuel element 5888, stainless-steel clad: Several concerning scratches and a large, repeatedly damaged scratch, indicating improper handling and threatening cladding integrity. No fission product release detected, but further handling may result in even minor damage sufficient enough to enable a release. It will not be used in the future unless thorough non-destructive evaluation concludes sufficient cladding integrity remains. Inspection records show small amounts of damage; however, [the records were] not fully indicative of the degree [of damage] observed during this inspection. The element has not been in service at this facility. It was obtained from the fuel repository at Idaho National Lab in 2016, which transferred the element from General Atomics, originally used starting in 1970. Fuel element 5671, stainless-steel clad: Appears to have oddly spaced and shaped bands of rust around the fuel section of the element. Coloration and lack of light reflection strongly suggest an abnormal corrosion, prominent on all sides of the element in varying degrees. Gently rubbing with a soft cloth resulted in minimal transfer of material, only some coloration but no discernable particulate, indicating the defects are integrated into the cladding and not freely releasable. No obvious mechanism exists to explain the features, though other elements on site have a similar pattern, none exhibit the degree of discoloration or loss of luster. The element was in storage at the facility but had been previously used. It will not be used in the future. It was originally purchased new from General Atomics in 1968. [The licensee is] still working through fuel inspections. There will likely be future updates. Notified NRR PM (Boyle), NPR Event Coordinator (Waugh), and USGS PM (Sutherland). |
Where | |
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U. S. Geological Survey (Usgs) Denver, Colorado (NRC Region 0) | |
License number: | R-113 |
Reporting | |
Non | |
Time - Person (Reporting Time:+1.95 h0.0813 days <br />0.0116 weeks <br />0.00267 months <br />) | |
Opened: | Johnathan Wallick 16:57 Jun 25, 2024 |
NRC Officer: | Sam Colvard |
Last Updated: | Jul 15, 2024 |
57191 - NRC Website | |
U. S. Geological Survey (Usgs) with Non | |
WEEKMONTHYEARENS 571912024-06-25T15:00:00025 June 2024 15:00:00
[Table view]Non Technical Specification Reportable Occurrence 2024-06-25T15:00:00 | |