DST provides geotechnical and geo-environmental services from offices in Canada (Toronto, Ottawa, Thunder Bay, Kenora, Sudbury), USA (Minneapolis) and the Middle East (Beirut). DST specializes in soft clay and peat engineering, insitu testing, heavy foundation design, slope stability, ground improvement, tailings dams, environmental site remediation, aggregate extraction, blasting engineering, demolition engineering, landfill design,soil or rock drilling, asbestos or mould abatement, indoor air quality, trenchless technologies, environmental assessments, fish habitiat studies, hydrogeology, sediment remediation, construction materials testing and inspection, asphalt testing, concrete testing, soil testing, masonry testing, compaction testing, pile testing.