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

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Moreover, although transportation-related impacts might be higher for island disposal, main-
land benefits would be significant because of the elimination of the need to dispose of TRU
wastes on the mainland.
The operation of the island repository itself is expected to be essentially the same as
that for a mined geologic repository. Therefore, the exposure of occupational personnel to
radiation should also be essentially the same. This exposure, during both normal and abnor-
mal conditions, is discussed in Section 5.6.
In the event that there were any nonoccupational people on the island, the maximum dose
received by any one of those individuals is expected to be similar to that received as a re-
sult of the operation of a mined geologic repository. However, because only a limited number
of nonoccupational people should be present, total nonoccupational radiological health ef-
fects for an island repository are expected to be considerably less than those for a mined
geologic repository.
Nonradiological Impacts. As indicated, impacts for island disposal should be similar to
those of the subseabed and mined geologic disposal options. However, for an island reposi-
tory in a relatively uninhabited area of the world, impacts would be significantly different
from those of the mined geologic repository. In that case, potential non-occupational
impacts would result primarily from transportation activities. Most transportation-related
impacts are expected to be similar to those from the subseabed disposal option and are des-
cribed in Section 6.1.4.4. That option, however, would not involve unloading waste material
and increased transportation that could cause additional impacts from island disposal.
Natural System Impacts
Investigation of candidate island disposal sites would involve drilling and geophysical
surveys, both on the island and in the adjoining offshore areas. During these activities,
natural and wildlife habitats could be disturbed. Access and exploration operations could
pollute both freshwater and seawater sources. Ecological effects could also arise from the
use of explosives for seismic surveying. These impacts could be minimized by identification
of sensitive areas and adequate planning.
Other ecological impacts, such as those described for the mined geologic repository in
Section 4.8, would occur on the island selected for final disposal. However, because of the
delicate balance of an island ecosystem, these impacts might require special consideration.
In addition, the construction and operation of the required transportation and repository
facilities would potentially impact the marine environment. These types of impacts have not
been extensively evaluated.
Another important consideration is that small island ecosystems provide no refuge for the
biota and ecosystems are much more easily affected by large-scale human activity. Further-
more, after the operational phase had ended, recolonization from outside sources would be far
more difficult, and would take longer, than for a continental region. Finally, the types of