November 3, 2022 | By Ellen O'Shea

In an advertorial in the September issue of Nuclear Engineering International, NAC International took time to explain the utility of its OPTIMUS packaging system, including its potential uses for important new high assay low-enriched uranium (HALEU) fuels, used in most advanced reactors.

“The small size of the OPTIMUS®-L packaging combined with its relatively large cavity size, payload capacity, and the ability to transport multiple types of radioactive materials such as uranium and contact handled TRU make it a versatile and useful package for the industry. Most importantly, it is operator-friendly,” wrote Mike Miller, Director of Business Development, Transportation Projects at NAC.

Furthermore, OPTIMUS-L is the “ideal packaging for transportation of different forms of HALEU fuels, including HALEU feedstock, in the form of metal ingots or UO2 powder, and TRISO compacts and pebbles,” said Miller.

An independent evaluation of OPTIMUS-L performed through collaboration with Idaho National Laboratory, Pacific Northwest National Laboratory and Oak Ridge National Laboratory and funded by the U.S. Department of Energy confirmed a single legal-weight truck (LWT) shipment of OPTIMUS-L packages will transport 250% more UO2 HALEU contents than would an LWT shipment using an alternative, more traditional Type B(U)F packaging.

NAC has also demonstrated a total of six OPTIMUS-L packages with the maximum number of TRISO compacts, can be transported in a single LWT shipment, while satisfying the regulatory requirements for criticality with significant margin, which Miller said, “far exceeds the capacity of the competition.” 

Using OPTIMUS-L will therefore translate to clear gains in expedience, efficiency, and cost, helping to improve the economics of advanced reactors requiring HALEU fuel.

The first commercial shipment using OPTIMUS-L took place in September 2022 and an application to amend the OPTIMUS-L U.S. Nuclear Regulatory Commission certificate for HALEU contents is in the process of submittal in 2022 with first transportation of HALEU planned for the first quarter of 2024.