The characteristics of spent nuclear fuel and high-level waste are described, and options for permanent disposal that have been considered are described. These include:
•disposal in a mined geological formation,
•disposal in a multinational repository, perhaps on an unoccupied island,
•by in situ melting, perhaps in underground nuclear test cavities,
•sub-seabed disposal,
•disposal in deep boreholes,
•disposal by melting through ice sheets or permafrost,
•disposal by sending the wastes into space, and

This report, Summary Report of Laboratory Critical Experiment Analyses Performed for the Disposal Criticality Analysis Methodology, contains a summary of the laboratory critical experiment (LCE) analyses used to support the validation of the disposal criticality analysis methodology.