Sioux City: 712-252-5132

Serving the Tri-State Area

Certified Testing Services Inc - Logo

Storm Lake: 712-213-8378

Soil Testing Compaction testing and inspection classification

Soil can be an extremely variable material which takes a high level of skill and training to identify changes in material. Our highly trained technicians and engineers will help to identify issues and help to resolve issues to keep your project on time. CTS uses the latest technology and equipment to keep your job moving forward and assure that the project specifications are being met.


With over 30 years of experience, we understand your need for a quick response time and we're happy to deliver your construction testing reports with a speed and accuracy that is unmatched in our industry. As a local, family-owned and operated business, you can hire us on a full-time or on-call basis, depending upon your needs.

Controlling soil variability

You can trust our staff for top-notch results. Call us to learn more about our soil services!

Sioux City:


or Storm Lake:


Structural integrity starts with a dependable soil foundation

Soil analysis services

  • Moisture-density relations

  • Compaction testing

  • Inspection and soil classification

  • Atterberg limits

  • Pile load tests

  • Pile placement inspection

  • Caisson placement inspection

  • Contract drilling services

  • EPS Foam Testing

  • Rammed Aggregate Pier Placement Inspection

  • Constant Head/Falling Head Permeability Testing

  • Consolidation Testing

  • Direct Shear Testing

  • Grain Size Analysis (Hydrometer) Testing

  • Soil Resistivity Testing (Lab and Field)

  • Dynamic Cone Penetrometer Testing