UMS®

Storage Solution for Virtually Every Fuel Type

NAC International designed and licensed the UMS® - Universal Multipurpose Systems – to handle virtually all types of Pressurized Water Reactor (PWR) and Boiling Water Reactor (BWR) fuel used in commercial nuclear power plants in the United States and around the world.

The UMS system is an evolutionary design based on the earlier-licensed NAC-STC basket and transport overpack designs. It has a capacity of 24 PWR or 56 BWR fuel assemblies and provides a single system that embodies the low cost of a storage-only system, the transportability of a dual-purpose canister-based system, and the canister benefits envisioned in the discontinued U.S. Department of Energy (DOE) Multi-Purpose Canister (MPC) program.

The UMS was the first U.S. system designed to meet the requirements of almost every U.S. utility, with involvement from U.S. operators and the worldwide fabrication team to ensure its successful launch and production.

The UMS was engineered to simply provide an excellent and safe system for storing and transporting nuclear fuel. The UMS has four primary components:

• Transportable storage canister
• Vertical concrete cask storage overpack
• Universal transport cask overpack
• Auxiliary equipment, including the transfer cask.

A transfer cask will move the transportable storage canister from the pool to the vertical concrete cask for storage, where it remains in the vertical concrete cask until it is transferred to the universal transport cask overpack at the time of shipment off-site.

NAC’s comprehensive fabrication program, and superior design and technology, resulted in uniformly reliable deliveries with the requisite high-quality level of more than 240 UMS systems.

NAC also incorporated other key features in its UMS design:

• A licensed impact limiter design that uses results from comprehensive drop tests on a quarter-scale model of the NAC-STC
• Multiple basket configurations to accommodate a full range of PWR and BWR fuels
• A hands-on transport and operations-based design perspective
• A comprehensive design review by engineers and manufacturers to ensure that system component designs are easily and efficiently fabricated