Solidification and storage of Hanford's high-level radioactive liquid wastes

When the present Hanford Waste Management program is completed in 1980, approximately 140 million liters of solid salt cake, produced by evaporation of aged radioactive liquid waste will be stored in underground mild steel tanks. Additionally, megacuries of 90Sr and 137Cs will have been removed from Hanford waste solutions, converted to solid 90SrF2 and 137CsCl, and stored underwater in doubly encapsulated metallic containers. Several alternative modes for long-term storage/disposal of these high-level wastes are presently being evaluated. For some of these modes conversion of the solids to immobile silicates of low water solubility may be desirable. Laboratory-scale studies of both low and high temperature processes for preparation of silicate minerals and glasses are in progress; status of the work is reviewed