Geoenvironmental engineering overlaps geotechnical and environmental engineering fields, dealing interactions between earth materials (soil and rocks) and a fourth phase such as chemicals. Geoenvironmental engineering concerns with the fate and transport as well as remediation of this additional phase (e.g., contaminants). Geoenvironmental engineering uses similar principles to investigate subsurface environment in order to characterize its physical, mechanical, chemical, and biological properties, and analyze, design, and construct substructures such as landfill and contaminant-containment facilities as well as soil and groundwater remediation.