Holtec International Storage Module Underground MAXimum Safety

Each HI-STORM UMAX Vertical Ventilated Module (VVM) provides storage of an MPC in the vertical configuration inside a cylindrical cavity located entirely below the top-of-grade of the ISFSI. The VVM, akin to the aboveground overpack, is comprised of the Cavity Enclosure Container (CEC) and the Closure Lid, as well as the interfacing structures.