A methodology has been developed for an overall evaluation of high-level waste disposal concepts. This methodology incorporates the following elements: technical feasibility, safety, research and development requirements, timing, costs, policy, environmental considerations, and public attitudes. Once the technical feasibility of a concept is established, the other elements are studied in parallel. Since system safety is the element of greatest uncertainty, a npre detailed description of its methodology is presented. The fault tree analysis technique is used in identification of mechanisms and probabilities of possible releases of radioactive waste constituents to man’s environment. A model of the geologic subsystem assists in quantifying the decontamination factors in the waste material transport process. In addition, a comprehensive dose computational model permits ready calculation of radiation doses to individuals and population groups for alternative waste disposal concepts.