A study was undertaken to evaluate conventional and novel methods for the ultimate disposal of spilled or released hazardous substances. Disposal methods studied include incineration, pyrolysis, landfilling, fixation, biological treatment, and chemical treatment. Applications of and problems associated with each of these disposal methods are discussed. Special emphasis is given to spills of highly toxic and persistent hazardous materials. An annotated matrix was prepared to provide a full assessment of conventional disposal options for each class of hazardous material and for mixtures thereof. The hazardous materials are grouped according to physical/chemical properties and placed in juxtaposition with the form (liquid, sludge) or composition of the spill residue containing the hazardous material (e.g., mixtures with water, grass, sand, debris, etc.). The disposal options are priority-ranked for each given set of conditions. The annotation describes each disposal option and evaluates the influence of spill-situation parameters on the disposal method with regard to effectiveness, cost, safety, availability of equipment and materials, and short and long-term hazards. Deficiencies in conventional disposal methods, such as secured landfills, are identified. An amended matrix, which supplements the matrix based solely on conventional methods, includes novel disposal methods that show strong potential for filling some of the gaps in existing disposal technology.