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

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ALTERNATIVE DISPOSAL CONCEPTS
geochemistry at depth, deep rock mechanical characteristics, and temperature effects that
would result from waste emplacement. On the other hand, extensive experience gained--for
example, through natural resource exploration and development, including mining, and a
variety of geologic exploration programs for other purposes--has provided a plethora of
information relevant to hydrologic and geologic characteristics of mined repositories at
depths between 500 m and 1500 m. Although this information is available and there have been
many studies for mined repositories, information for depths beyond 1500 m becomes signifi-
cantly less available as depth increases.
The second comment suggests that more detail should be considered in the discussion of
of impacts that may be attributable to alternatives. Such detail is included to the extent
practicable in Section 6.1 of the final Statement.
Although the comments address two different subject areas, an important relationship
is noteworthy; namely, both comments illustrate the significantly different levels of infor-
mation that exist for mined repositories as compared to all of the other alternatives being
considered. The mined repository concept has been the subject of a large number of studies
over many years. The studies include transportation logistics, detailed repository design,
waste and host rock interaction, to name a few general categories. The most advanced of the
alternative concepts, subseabed, has only recently advanced to the stage where host media
and waste material interactions are being studied.
Discussions presented in Section 6.2 and Chapter 7.0 of the final Statement address the
issue of relative stage of development and its importance to the evaluation of alternatives
and to the selection of a programmatic option for disposal of radioactive waste.
Draft p. 3.2
Issue
This entire section appears to be largely speculative. The comment as to the spec-
ulative nature of the discussion applies to Sections 3.2, 3.3, 3.4, and, in fact, all of
the rest of Chapter 3.0. (113-EPA)
Response
Alternative concepts for the disposal of radioactive waste are at various levels of
development with the mined repository being the most developed. For most of the concepts
there are large uncertainties regarding their characteristics and attributes. These uncer-
tainties are discussed in Section 6.1 of the final Statement. Section 6.2 presents a
comparative assessment of alternatives in which the current status of development, and
therefore uncertainty, is discussed. These sections also offer the reviewer a synopsis of
a number of the various alternatives that have been proposed for the disposal of radioac-
tive waste and a summary of the rationale for selection of the mined repository as the