SEVERE ACCIDENT CLEANUP: THE CONTINENTAL-SHELF SEABED DISPOSAL OPTION

摘要

A large fraction of the economic and political costs of the Fukushima accident are associated with the loss of land and cleanup activities. The lack of high-volume low-cost waste disposal technologies (1) limits the rate of land decontamination, (2) determines when all evacuations will end, and (3) drives cleanup costs which ultimately determines the practical degree of cleanup that can be undertaken. Low-cost disposal methods for high-volumes of heterogeneous, slightly-contaminated wastes with small radioactive hot spots do not exist. Advancing technologies and better understandings of how radioactive disposal sites perform have created a new disposal option: continental-shelf sub-seabed disposal. Such an option is applicable to the Fukushima site, would be applicable to most of the world, and is viable for both nuclear (Fukushima) and chemical (Severno) accidents. Because of limited use of the sub-seabed, it is the most available nearby land for a disposal site in much of the world. The expectation is that sub seabed disposal will have better performance than land-based disposal sites because of several unique characteristics: limited or no groundwater movement, saltcrete in the disposal site to assure groundwater isolation from seawater by density, saltcrete to preserve wastes in an unchanged state over time, and ocean isolation.