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 Start dateReporting criterionTitleEvent descriptionSystemLER
ENS 4366619 September 2007 04:00:0010 CFR 21.21, Notification of failure to comply or existence of a defect and its evaluationPart-21 Dry Cask Canister Documentation Lost

TN identified and documented in Supplier Finding Report 2007-111 that our fabricator, GE-Hitachi Nuclear Energy Americas (GHNEA), had provided inadequate fabrication records resulting in a nonconforming condition relative to the possibility of undocumented Temporary Weld Attachments (TWAs) to the confinement boundary of a loaded NUHOMS 32PTH Dry Shielded Canister (DSC) at Surry Power Station. This condition involves a lack of documentation for use of qualified welders, approved welding procedures, approved weld filler material and compatible TWA base material, as well as a lack of the required liquid penetrant surface examination report subsequent to TWA removal. Such documentation is required per Article NB-4435 of the ASME B&PV Code Section III, which is a design feature embedded in the Technical Specifications for the NUHOMS HD license. Based on the preliminary evaluation, it is concluded the subject DSC is capable of performing its design functions involving the structural integrity of the confinement boundary, heat removal, shielding and criticality control associated with the safe storage of spent nuclear fuel. Four DSCs were shipped (three to Surry and one to North Anna) with insufficient documentation. The documentation for one of the Surry canisters was subsequently found. Of the remaining three DSCs, one at Surry, was loaded with spent fuel.

  • * * UPDATE FROM TRANSNUCLEAR (NEIDER) TO HUFFMAN AT 1537 EST ON 12/20/07 * * *

As of 1530 EST on 12/19/07, the licensee determined that a second Dry Shielded Canister (DSC) shipped to Surry that is loaded with spent fuel has undocumented Temporary Weld Attachments (TWAs). The original report above noted that only one DSC (serial # DOM-32PTH-001-C) with TWAs had been loaded with spent fuel at Surry. The licensee had believed that documentation for another one of the loaded DSCs had been subsequently found. Upon further review, Transnuclear has determined that Surry DSC, Serial# DOM-32PTH-003-C (loaded with spent fuel), has other undocumented TWAs that were not initially recognized. Furthermore, two additional DSCs were shipped to Surry that have undocumented TWAs. Specifically, a total of six casks have been shipped with the undocumented TWAs of which five were sent to Surry and one to North Anna. Two of the five at Surry have been loaded with spent fuel. A hold has been place on the three remaining empty DSCs at Surry and one empty DSC at North Anna. In addition, all DSCs still at the licensee's fabricators with possible undocumented TWAs have also been placed on hold. Based on this new information, the licensee is expanding the scope of its initial report. R2DO (Shaeffer) and R1DO (Henderson) notified. In addition, NMSS (Pstrak), FSME EO (Mohseni) and Part 21 coordinators (Hodge and Thorpe) have been notified.