Long-term safeguards for plutonium in geologic repositories

The level and duration of safeguards for geologic repositories will depend on the relative difficulty of reclaiming fissile material, compared to utilizing alternate sources. Old spent fuel, aged over 300 years, merits particular attention because of its relatively high plutonium concentrations and low radiation levels. Several parameters must be predicted to provide input for current nuclear fuel cycle policy decisions, including future maximum tunneling advance rates, noise generation, and cost; difficulty and cost of plutonium separation: and the utility of separated repository-grade plutonium for nuclear explosives. Mining of old spent fuel repositories will provide a new class of proliferation risks for future generations: with smaller capital and manpower investments, the potential plutonium production rates exceed significantly the rates possible with dedicated reactors and reprocessing