The NRC has amended its 10 CFR 72 regulations to approve the technology of NAC International’s Universal Multi-purpose Canister System (NAC-UMS). This will allow utilities to use the system under a general licence, without site-specific approval. The approval becomes effective 30 days after publication in the Federal Register.

The UMS can accommodate all US and international standard LWR spent fuel, and is also being licensed to carry nonstandard, including high-burnup, fuel.

NAC is under contract to supply more than 80 UMS units to several US operating and decommissioning stations. The UMS design is based closely on the first dual-purpose system licensed by the NRC, the NAC-STC. The new technology relies on a stainless steel-encased basket that can safely store spent fuel in a concrete storage overpack at an independent spent fuel storage facility. The technology includes a steel-lead-steel transport overpack for transportation to a central interim storage facility or to the final repository.

NAC is under contract to deliver its NAC-UMS system to the Maine Yankee plant. Earlier this year the company launched the development of an advanced UMS, which will allow up to 69 BWR assemblies or 32 PWR assemblies to be loaded into a single canister, while accommodating higher burnup and higher enrichment fuels.