Holtec International Storage Module Consolidated Interim Storage
HI-STORM CIS (Holtec International Storage Module Consolidated Interim Storage) is the next generation underground storage design that will house used fuel packaged in any canister supplied by any cask vendor.
The HI-STORM CIS Vertical Ventilated Module (VVM) stores two Multi-Purpose Canisters (MPCs) in a vertically stacked configuration in each cavity. Stacking two canisters ultimately halves the required storage area.
A 14 acre HI-STORM CIS ISFSI can store 4,000 canisters containing more than 50,000 tons of uranium. The HI-STORM CIS features a monitored underground storage cavity with the used fuel’s decay heat passively rejected to the ambient air above and its radiation contained within the subgrade in which the canisters are stored. The radiation released to the environment from the HI-STORM CIS facility storing vast quantities of used fuel is negligibly small.