BPMI (Bechtel Plant Machinery Inc.) moved into the original 129,000 square foot building after completion of an extensive renovation in 2007.
In 2009 Elmhurst completed a 50,000 square foot addition to the existing building, and in 2019 Elmhurst completed a second 90,000 square foot addition, providing BPMI with a total of 269,000 square feet. The site is home to more than 1,000 engineers and support personnel.