Geotechnology Inc. is greatly expanding with the acquisition of Thelen Associates. The transaction closing became official Aug. 17.

Thelen Associates, an engineering firm founded in 1971, provides geotechnical engineering and construction materials testing services regionally in Kentucky, Ohio, Indiana and Tennessee. Since 1971 Thelen has provided engineering, testing and construction review services for more than 35,000 projects. Currently, Thelen has 108 employees operating from four offices.

“This business decision was made based upon careful consideration of how to best augment our resources, assets and service lines,” says Geotechnology President and CEO Ed Alizadeh. “Currently, Thelen Associates does not offer geophysics or environmental services, which have been highly sought after services by our other clients. With more resources available, we will be able to help our clients solve problems and grow their businesses.”

With the addition of Thelen, Geotechnology will have 280 employees operating from 10 offices. The company anticipates that number will increase with expanding project opportunities. This expansion allows Geotechnology and Thelen to efficiently and effectively serve clients throughout the middle part of the country.

Thelen's projects include transportation infrastructure; commercial, institutional, industrial and retail developments; water/wastewater; dams and levees; and major sports facilities.

Geotechnology’s purchase of Thelen’s assets is part of a long-term strategic plan of geographic expansion. Founded more than 30 years ago in St. Louis, Geotechnology opened offices in Illinois and Kansas as demand for its services increased. In 2010, Geotechnology purchased Hall, Blake & Associates in Memphis. Earlier in 2015, the company opened two new branch operations in Oxford, Miss. and Jonesboro, Ark. The Thelen acquisition provides a greater presence to Geotechnology’s current Midwest and South operations.

“We are excited to be a part of the Geotechnology family,” says Thelen Associates President Don Thelen. “The pace of design and construction projects is more aggressive with each passing year. Increasing our capabilities, specialized staff and technologies will afford us even more opportunities and successes.” 

Geotechnology is a professional corporation offering a range of consulting services in applied earth and environmental sciences, including geophysics, water resource management, geotechnical and environmental engineering, materials testing and drilling. Geotechnology is based in St. Louis. For more information, visit