To prepare for the electric vehicle future, General Motors has been rapidly expanding its manufacturing capabilities in the segment. In the fall of 2020, Spring Hill, Tennessee was announced as the next EV plant expansion location. Independence Excavating (IX) was chosen as the site civil contractor for this large, complicated, and fast-paced project by the General Contractor, Walbridge out of Detroit, Michigan.

The original Spring Hill plant was built in the late 1980’s by the Saturn Corporation, a subsidiary of General Motors. Over time and through billions in investments, the plant has grown to become the largest GM plant in North America producing Cadillac and GMC mid-size SUVs. As GM pivots to prepare for an electric vehicle future, Spring Hill was chosen as an expansion location to build the new Cadillac Lyriq, an all-electric SUV. To keep up with the rapidly evolving car market, the project is being built directly next to the existing facility with an extremely aggressive schedule, while maintaining full operation of the existing plant. The difficult nature of the project proved to be a good match for IX and we were awarded the site civil contract in October of 2020.

The project got off to a lightning start. The project was publicly announced October 20, 2020 and IX mobilized over 50 pieces of equipment in a few short weeks and broke ground on November 9, 2020. The scope of the project includes two large new construction buildings that will house a 415,000 square foot paint shop and a 325,000 square foot body shop. To support the construction of these two structures, IX is responsible for the creation of 14 acres of new plant parking to replace the parking displaced by the new construction. To support the lots, IX will build 9,000 linear feet of curb, 28,000 square feet of sidewalk, 15,000 linear feet of site lighting conduit, 83 precast light poles bases and all associated line striping and site signage. A new 60-foot long pedestrian bridge will be installed in conjunction with a hybrid soil nail and MSE wall to allow access to the existing plant upon completion of the new facilities. Finally, a 2,700-foot long section of the 4-way divided limited-access highway around the plant needs to be relocated to support the new plant building and parking lot layout.

For the new structures, IX will perform all of the earthmoving, grading, and exterior utility operations to facilitate the construction of the buildings. The site work requires 575,000 cubic yards of earthmoving along with 150,000 cubic yards of drilling and blasting. Site storm sewer will consist of over 10,000 feet of RCP pipe varying in size from 12” to 60” along with 52 precast storm inlets and manholes. Site fire mains include 9,000 feet of 12” C-900 along with 22 fire hydrants and all building fire protection risers. To support the building construction, a tremendous amount of coordination is required to bring all the pieces of the puzzle together and keep the project on schedule.

To meet the demanding schedule, IX crews have worked 7 days a week for months through the Tennessee winter. IX has had an onsite presence of 50 to 140 tradesmen, field supervision, and subcontractors throughout the project to keep up with the work requirements. To maintain operations in the plant, a tremendous amount of communication and coordination has been required to share our strategy with Walbridge and General Motors so that our work and plant production can happen simultaneously. To date, the project has remained on schedule and the plant has not missed out on any production due to our work on the project. 

Earthmoving and grading operations are complete as well as the new parking lots. Building construction began ahead of schedule and our focus is on exterior utility installation. Our team continues to keep our foot on the gas and looks forward to the completion of another difficult and demanding project for our customer. IX is in a great position for a strong finish to the project.