The new sonic drill rig on site to perform groundwater investigations near Fort Jackson, South Carolina Jan. 26. The drill rig is a piece of high-tech machinery that is the only one of its kind within the federal government. The Savannah District uses the sonic drill in subsurface and geotechnical investigation projects, serving various state and federal customers throughout the nation. The new sonic drill gives Savannah's drilling team increased capability to drill through all types of soils and most rock.