Engineering & Testing Consultants, Inc. (ETC) was founded in Prescott in 1981 and has provided professional engineering and construction support services to various public agencies and the private sector throughout Yavapai County and northern Arizona. We are the only locally owned geotechnical engineering firm in Prescott. With our near 30 year history in Prescott, we have an extensive knowledge of the soil conditions within Prescott and northern Arizona.