Established in June 1999, Yeh and Associates, Inc. is a full-service geotechnical engineering and construction management firm based in Colorado with six offices (Denver, Colorado Springs, Durango, Grand Junction, Glenwood Springs, and Greeley) and two in California (Grover Beach and Ventura). The firm currently employs 150 professionals with extensive professional experience in geotechnical, geological, and environmental engineering, materials testing, construction inspection, observation, and management support services. Yeh and Associates is a certified Disadvantaged Business Enterprise (DBE) for our Construction Services group.