Sioux City: 712-252-5132

Serving the Tri-State Area

Certified Testing Services Inc - Logo

Storm Lake: 712-213-8378


With over 30 years of experience in geotechnical engineering, Certified Testing Services Inc is proud to have some of the best engineers and field technicians in the industry on our team.


To serve you better, we're continually investing in the training and personal development of all our valued staff. Maintaining current industry certifications is a must for our team! If you want to get to know us better, please click on the links below to read more about our dedicated staff members!

Learn More About Our Staff Members

Sioux City Construction Testing Staff

Do you have a question on our services? Call:

Sioux City



Storm Lake


Sioux City Geotechnical Engineers

Sioux City Drilling Staff

  • Jack Holbrook

  • Kelly Andrie

  • Bill Church

  • Adrain San Nicolas

  • Les Hinze

  • Brandon Renken

Storm Lake Staff

Administrative Staff

  • Sarah Trucano

  • Anna Danderand

  • Kathleen Martin

  • Ashley Syndergaard

staff photo