Terracon’s Colton office was originally founded as CHJ Consultants (CHJ) in 1964 and was acquired by Terracon in 2016. We service projects throughout Southern California, offering a wide range of geotechnical and engineering geologic investigations, soils, materials testing and inspection, and in-house laboratory testing of soils and construction materials.
Our engineering geology group are recognized as experts in the local conditions. By collecting existing subsurface information from the US Geological Survey and the California Division of Mines and Geology, we are able to identify seismic and geologic hazards that might impact the design, construction, and life cycle of projects.
Colton works in conjunction with our Orange County office (located in Tustin) to provide extensive environmental, hazardous materials, and industrial hygiene consulting.
Our in-house laboratories are inspected and approved by the Cement and Concrete Reference Laboratory (CCRL), the American Association for Laboratory Accreditation (A2LA), AASHTO Materials Reference Laboratory (AMRL), Caltrans, DGS RESD, the US Bureau of Reclamation, the U.S. Forest Service, and through Terracon in-house audits.