NRC confirms Nov. 9 effective date for NUHOMS spent fuel cask amendment

The U.S. Nuclear Regulatory Commission has confirmed that its direct final rule on a TN Americas, LLC spent fuel storage system takes effect on November 9, 2026. The rule was published in the Federal Register on August 26, 2026 (91 FR 54941).

The rule adds Amendment No. 19 to Certificate of Compliance No. 1004. That certificate covers the Standardized NUHOMS Horizontal Modular Storage System for Irradiated Nuclear Fuel, which sits in the NRC's "List of approved spent fuel storage casks" in part 72 of title 10 of the Code of Federal Regulations.

What Amendment No. 19 changes

The amendment provides for an improved basket design for the 61BTH, built with staggered plates. The NRC says the design is similar to the 24PTH Type 3 basket approved in Amendment 18 of CoC 1004, and to the EOS 37PTH and 89BTH baskets approved in CoC 1042. According to the NRC, the design will simplify construction, reduce weight and improve fabricability. The amendment also makes editorial corrections, consistency fixes and terminology clarifications.

How the NRC handled the comments

The direct final rule would take effect on November 9 only if no significant adverse comments came in. The NRC received and docketed three comment submissions on the companion proposed rule (91 FR 55028), and concluded none were significant and adverse.

One commenter raised a higher heat load as a significant change. The NRC said it reviewed that load, documented it in section 5.1.1 of the safety evaluation report, and found it acceptable. Another commenter questioned the lack of site-specific analyses. The NRC answered that specific environmental assessments are not required because 10 CFR 51.22(a)(12) contains a categorical exclusion. That commenter also argued the changes would make appreciable differences in cask performance. The NRC said its staff evaluated all proposed changes and recorded the results in the safety evaluation report.

The remaining comments were outside the scope of the rulemaking and did not oppose the rule or propose a change to it, the certificate of compliance or the technical specifications.

The confirmation appears at 91 FR 69205 under Docket ID NRC-2026-2806 and is dated October 30, 2026. The final amendment, technical specifications and safety evaluation report are in the NRC's ADAMS system under Accession No. ML26282A009.