Hyundai Metaplant Sets Benchmarks for Speed, Geotechnical Engineering

Client

Hyundai Motor Group 

Location

Ellabell, Ga. 

Challenge

Hyundai Motor Group set out to build the largest electric vehicle manufacturing plant in the United States and the only one to combine EV and battery production at the same campus. The two-year schedule was ambitious, and the site conditions were unforgiving.

The 3,000-acre coastal site near Savannah, Georgia, included loose sands, soft clays, and a shallow groundwater table. These subsurface conditions raised concerns about earthquake-related soil liquefaction, long-term settlement under heavy structural loads, and stability during deep excavations.

The scale added complexity. Fourteen buildings totaling 7.6 million square feet were designed and contracted separately, with teams working across the U.S. and Korea. Every geotechnical recommendation needed to consider safety, constructability, and cost control without slowing progress on one of the fastest large-scale industrial developments ever attempted.

Solution

Terracon partnered closely with Hyundai, contractors, and design teams to reduce risk while keeping the project moving. Our approach emphasized rigorous site characterization, data-driven design, and close collaboration in the field.

Success hinged on several factors, among them: 

Comprehensive site characterization: A robust geotechnical investigation was essential for developing accurate soil profiles, settlement predictions, and seismic site classifications. Methods included seismic cone penetration testing (SCPT), multichannel analysis of surface waves (MASW), extensive lab testing, and 435 soil borings.

Seismic and liquefaction risk mitigation: By refining the seismic analysis, we were able to justify a lower liquefaction risk. All buildings were supported on piles extending below liquefiable layers, eliminating the need for costly ground improvement programs or specialized structural designs, saving both time and money.

Customized foundation solutions: Different structures required different solutions. Deep foundations — primarily auger-cast piles — were selected to control settlement and address liquefaction risks. An innovative hybrid solution using displacement-type cast-in-place rigid inclusions (CGEs) in the upper sands, combined with deeper auger-cast rigid inclusions for slab support, reduced pile lengths, and optimized costs while maintaining performance.

Adaptability: The team overcame significant challenges, including site drainage limitations, groundwater control, and extreme weather events such as Hurricane Helene. They adapted foundation strategies — such as using driven steel piles for excavation support — to maintain schedule and safety.

Throughout the project, Terracon’s proprietary Compass data-sharing platform kept stakeholders aligned, improved communication across international teams, and helped avoid costly delays.

Results

Less than two and a half years after Hyundai entered an agreement with the State of Georgia to create the facility, the first vehicle rolled off the assembly line. Terracon won state and national American Council of Engineering Companies (ACEC) awards for the project, recognizing the innovation, collaboration, and engineering excellence that helped redefine what’s possible for large-scale industrial development.

Terracon acknowledges the collaboration of: Hyundai Motor Group, Berkel & Company Contractors, Inc., Keller North America, the structural and civil design teams, Georgia’s Department of Business Development, the Savannah Economic Development Authority, the Savannah Harbor-Interstate 16 Corridor Joint Development Authority, and Terracon management and dozens of engineers and technicians, whose partnership and expertise were instrumental in delivering this project.