Civil Construction of the Underground Storage Facility (HI-STORM UMAX) at Callaway is Underway

We are pleased to report that the construction of a 48-cavity HI-STORM UMAX storage facility at Ameren’s Callaway nuclear plant is proceeding apace. The photograph below shows the status of civil construction work. The first loading campaign, consisting of six MPC-37 canisters, is scheduled to begin in mid-June 2015. The site construction is expected to end in January 2015 and the dry run is scheduled for April-May 2015.

Callaway Nuclear Plant HI-STORM UMAX Construction Site

The underground storage technology was developed by Holtec in the aftermath of 9/11. The storage system essentially consists of a 25 feet thick monolithic block of concrete with embedded thick walled metallic “cavity enclosure containers” fortified from above and below by thick reinforced concrete mats, making the storage system essentially indifferent to the height of the subterranean water table.

A HI-STORM UMAX ISFSI in Perspective View
Humboldt Bay ISFSI in Perspective View

Other beneficial attributes of HI-STORM UMAX are: (i) The system would shrug off any terrestrial earthquake recorded on earth without any risk of radiation release: Indeed, the licensing basis for the system’s general certification bounds design basis earthquakes for all current U.S. nuclear plant sites; (ii) Situated deep below the ground, the stored MPC is firmly inaccessible to acts of terror or destructive eruptions of nature; (iii) Flood, fire, and other vagaries are likewise reduced to little more than operational nuisance.

Wind, another bane of ventilated storage systems, has been marginalized into a second order effect using an artful design.

“We are proud to be building a below-ground fortress for storing fuel at Callaway. Because the threat to nuclear installations is unlikely to diminish in the foreseeable future, we salute Ameren for their farsighted view in selecting HI-STORM UMAX for Callaway’s on-site storage facility”, says Holtec’s Director of Site Services, Steven Soler.

Callaway’s underground storage site is preceded by a non-ventilated underground facility (for low heat loads) at PG&E’s Humboldt Bay, installed and operating since 2007 (see photo).

Humboldt’s aerial view (see below) illustrates the vanishing visual profile of the underground system (Dear reader: can you spot the ISFSI?).

The underground storage technology pioneered by Holtec in the past decade is covered by U.S. patents assigned to the Company: Patent Numbers 8,351,562B2; 7,933,374B2; 7,676, 016B2; 7,590,213B1; and 7,068,748B2.

Humboldt Bay hosts the World’s First Underground Storage Facility by Holtec (2007)
Media Files: HH 29.07

Written by Amy Grant

Amy Grant is a graphic designer and web developer. She is the founder of the Southwark Historical Society, a volunteer based group that studies the Southwark Historical District located in Philadelphia, Pennsylvania.