Management of Commercially Generated Radioactive Waste - U.S. ...

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Ion Transport in the Sediment. More data would be required regarding the rates at which
the radioactive ions transfer through the sediment. Studies and empirical data would be re-
quired to determine the thermal interaction with canister materials and wastes, conduction,
and convection through the sediment.
Ion Transport to the Biosphere. The paths and rates at which the radioactive ions could
transfer from the sediment, through the benthic boundary layer, and into the water column are
not known. Both mathematical models and empirical experiments would be required to obtain
this information. Modeling would also be required to determine a realistic rate of migration
up the water column.
Sediment Mechanical Requirements. The subseabed sediments that would be candidates for
nuclear waste disposal are between 4,000 and 6,000 m (13,000 and 20,000 ft) below the ocean
surface. Further information would have to be acquired regarding their macroscopic (as well
as microscopic) structural characteristics. These characteristics include sediment closure
after emplacement and long-term sediment deformation and buoyancy resulting from heating.
R&D Requirements
The SDP is divided into seven R&D fields of study (see Sandia 1980), each with numerous
subdivisions. As far as funding and the state of technology allow, all of these studies are
being pursued simultaneously, though not all at the same level of detail. An eighth field,
safeguards and security, would be established later as the results of the other seven stu-
dies become known. Brief descriptions of these eight studies which define R&D requirements,
follow:
Site Studies. Current studies include evaluation of North Atlantic and North Pacific
oceanic areas that meet site suitability criteria. From these areas, certain study locations
have been, and will continue to be, identified for more intensified study.
Environmental Studies. Environmental studies include physical and biological oceano-
graphy. They focus on analyzing physical characteristics of the water column from the ocean
surface to the sediment surface, and on gathering all pertinent information about the marine
life that inhabits the water column. The ultimate purpose of these studies is to determine
whether, and to what degree, the physical and biological characteristics of the ocean would
accelerate or slow the transport of accidentally released radionuclides to man's environment.
Multibarrier Quantification. The multibarrier study includes the sediment, the canis-
ter, and the waste form, both immediately adjacent to the waste container and further afield,
to determine their natural characteristics. Again, the ultimate purpose is to learn whether,
and to what degree, they would allow released radionuclides to be transported. A second
purpose is to learn how they would react to the heat and radiation generated by a waste con-
tainer, as well as to any engineered modification to the sediment such as artificial closing
of the emplacement hole.