Plasma torches generate sufficiently high temperatures that virtually any organic material will pyrolize or volatilize, and any inorganic material will volatilize or break down into stable components in a molten state. If sufficient siliceous materials are present, the residual inorganic materials will form a vitrified product upon cooling. This byproduct glass is typically structurally stable and readily passes USEPA leachability tests, demonstrating the usefulness of this technology for remediating contaminated soils.