Idaho Falls, ID

Idaho National Laboratory, Integrated Waste Treatment Unit (IWTU)


The Idaho Cleanup Project involved installation of an Integrated Waste Treatment Unit (IWTU) that implemented a prototype technology. The IWTU processes radioactive acidic sodium-bearing waste and converts it into a solid carbonate product. As engineer of record, SGH designed two of the primary buildings to accommodate the system and supported completion of the project on an expedited schedule.

The IWTU facility includes a 40,000 sq ft steel braced-frame structure that houses off-gas, mechanical, and processing areas, and also supports a 20-ton bridge crane. A high-hazard reinforced concrete structure with thick walls supported on an extended mat slab sits below the crane and contains process and packaging cells (PPC) and a loading vault. A transfer bell crane travels between the PPC and a separate cask loading area. For this project, SGH completed the following:

  • Analyzed and designed the following:
    • PPC facility in accordance with DOE-STD-1020-02 for Performance Category 3 (PC-3) requirements for seismic soil-structure interaction behavior and nonseismic dead, live, and temperature loadings
    • Foundation and structure of the steel building for enhanced code requirements to prevent collapse onto the PPC
    • Runway for the 20-ton bridge crane
  • Foundation and framing for the transfer bell crane
  • Reviewed the structural design of the bridge crane for compliance with ASME NOG-1 codes
  • Specified geotechnical requirements and reviewed geotechnical reports
  • Performed structure-soil-structure interaction analysis to generate design input and in-structure response spectra
  • Support to develop concrete mix design and testing plan
  • Provided construction support and administration services
  • Presented and defended the project to the Defense Nuclear Facility Safety Board (DNFSB), the DOE
  • Environmental Management headquarters, an owner-established Blue Ribbon Panel, and peer reviewers

Project Summary



Completion Date
New Construction
Structures | Advanced Analysis
Science & Defense
Thor Treatment Technologies, LLC | CH2M-WG Idaho, LLC
Specialized Capabilities
Building Design | Seismic Engineering | Nuclear

Key team members

Daniel Eggers
Daniel Eggers
Said Bolourchi
Said Bolourchi
Senior Principal