Terradyne is a leading provider of geotechnical & environmental engineering, construction materials testing and civil site de ... sign services. With eight offices in California, Colorado, Texas and Virginia (Washington D.C.), we have completed projects of all sizes throughout the United States. Specialties: Geotechnical Engineering Environmental Engineering Construction Materials Testing Terradyne has completed projects in California, Arizona, Colorado, Wyoming, Oklahoma, Texas, Arkansas, Louisiana, Mississippi, Pennsylvania, Virginia, West Virginia and Maryland. read more