The HI-STORM FW (Flood & Wind) MPC Storage System has successfully completed the NRC’s safety review and rulemaking process, including the public comment period (a unique feature of licensing in the United States) and is scheduled to be certified for general use under 10 CFR 72 Subpart L on June 13, 2011.

The HI-STORM FW System is the second Holtec system to use the nanotechnology based MPC basket material, METAMIC-HT, to elevate the neutron absorption capacity and the heat rejection capacity to nearly 50% above that possible with previous systems using a stainless steel basket (see table below). The first NRC-approved Holtec cask, which uses Metamic-HT, is the HI-STAR 180 dual transport/storage cask, which was licensed for transportation in 2009 (USNRC Docket No. 71-9325).

As a result of the outstanding capabilities of METAMIC-HT, it will now be possible to prepare a plan to de-fuel the pool in which fuel, with as little as 3.5 years of age, may be transferred to dry storage. The excellent flood and wind resistance attributes of the HI-STORM FW are arguably the most prized characteristics in the post-Fukushima age.


Key HI-STORM FW System Data
Heat Load
Capacity Min. B-10 areal
density (g/cm2)
Total Damaged or
Fuel Debris
MPC-89 BWR 46.36 89 16 0.039 65.0
MPC-37 PWR 47.05 37 12 0.058 68.2


The record-setting performance metrics of HI-STORM FW, illustrated by the above table, are made possible by the wondrous mechanical and nuclear properties of METAMIC-HT. METAMIC-HT has roughly 10 times the thermal conductivity, about one-third of the density, and about two-thirds of the yield strength of stainless steel; and in neutron capture capacity it is peerless. In addition, loading operations are significantly simplified since the need for auxiliary cooling water during all short-term operations is eliminated. The low weight of the METAMIC-HT fuel basket frees up valuable weight for shielding in the transfer cask.

A 270,000 sq. ft. manufacturing plant in Orrville, Ohio (see photo) has been built by Holtec to support the large scale production of METAMIC-HT to meet the growing global demand for dry storage systems. The Orrville plant is expected to employ over 500 workers.

The HI-TRAC VW transfer cask, designed for use in the HI-STORM FW system, is configured to maximize the amount of shielding around the MPC during loading operations while staying within the constraint of an individual plant’s crane capacity.

HI-STORM FW System is engineered to be fully fungible with the HI-STORM 100 System, utilizing the same loading procedures, same ISFSI pad, and most of the same ancillaries.

The first HI-STORM FW Systems will be delivered to SCANA’s VC Summer Station in South Carolina under a contract established between the utility and Holtec earlier this year.

Run-out Table for the Extrusion Press Shown Below
Run-out Table for the Extrusion Press Shown Below


Extrusion Press (One of Four) at Orrvilon, Ohio (Home of METAMIC-HT)
Extrusion Press (One of Four) at Orrvilon, Ohio (Home of METAMIC-HT)
Media Files: HH 26.09