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

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described for the mined geologic concept. The other land area that could be impacted is the
region of dry barren valleys in Antarctica. If wastes were placed in this area, impacts would
be very similar to those of the mined geologic repository. The major difference would be that
the ground-water regime in Antarctica would mostly affect remote frozen ground-water systems.
Terrestrial ecosystems in the ice sheet regions under study for disposal sites are
limited in diversity. Severe climatic conditions limit most organisms to the seaward margins
of both Greenland and Antarctica. Consequently, the potential for impact to terrestrial
organisms in the ice sheet disposal is quite limited. Potentially more significant are the
long-term ecological effects of any accidents that would occur on the land mass where the
wastes were generated. As described in Section 5.6, these impacts should not be significant
unless an accident or encroachment occurs.
6.1.5.6 Cost Analysis
The cost of depositing nuclear wastes in ice sheets is currently expected to be rela-
tively high; higher, for example, than the cost of geologic emplacement in the U.S. This is
primarily because of the high costs for R&D as presented in Section 6.1.5.3. Capital, oper-
ating, and decommissioning cost estimates are presented below.
Projected Capital Costs
Projected capital costs for ice sheet emplacement of 3000 MT/yr of spent fuel, or the
wastes recovered from processing that amount of fuel, are $1.4 billion to $2.3 billion as
shown in Table 6.1.17.
Projected Operating Costs
Projected operating costs for the emplacement of 3000 MT/yr of spent fuel or HLW are
shown in Table 6.1.18.
Decommissioning Costs
Decommissioning costs associated with contaminated equipment would probably be limited
primarily to the shipping casks used to transport waste canisters for ice sheet disposal.
These costs are estimated at $9.7 million, which is 10 percent of the initial capital cost of
the shipping casks. Costs for decommissioning other facilities and equipment are assumed to
be similar to those for other waste disposal alternatives.
6.1.5.7 Safeguard Requirements
Because the reference concept uses both ice sheet and mined geologic disposal, its
implementation would require safeguarding two separate disposal paths. The risk of diver-
sion for the meltdown concept would be basically a short-term concern because once the waste
had been successfully disposed of in accordance with design, it would be considered irre-
trievable. For the anchored and surface storage concepts, although the waste would be con-
sidered retrievable for as long as 400 years, the harsh environment in which it would be