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

6.2
annual throughput or a common environment. As an example, the well injection concept section
presents radiological impact information extracted from a reference which addresses the
impacts of intermediate level waste disposal. This is done to provide the reader with
related information that may be important to the understanding of the concept. In addi-
tion, the space disposal and transmutation concepts require chemical processing of spent fuel
to prepare waste for disposal or elimination. Accordingly, comparisons between these con-
cepts and, for example, others not requiring processing would be difficult. For instance,
transportation costs in the processing case could not be compared with those for disposal of
spent fuel.
Four of the concepts (very deep hole, rock melt, space, and subseabed), however, were
covered in a common reference and thus have a common basis. The other options are not nor-
malized because, for example, while linear extrapolation to a higher or lower quantity of
waste handled may result in a more or less conservative estimate of impacts and costs for a
particular option, it may also bias any comparative analysis for or against that concept.
Also, the descriptions, impacts, and costs that have been reported for some of the alterna-
tives are incomplete because of the early stage of the alternatives' technical development.
In addition to being, in many cases, incomplete, the cost and impact data should be con-
sidered speculative. For example, the costs projected for the development of an alternative
are generally based on judgment regarding the current state of technical uncertainty for the
alternative. In practice, many such cost estimates do not adequately anticipate the expanded
scope of activities'that may result as additional uncertainties and issues are identified in
attempts to resolve the original set of uncertainties. It was felt, therefore, that manipu-
lating costs and impact information may indicate more significance than is warranted.
The disposal methods along with rates used as a basis for defining each of the alterna-
tives, including the mined geologic repository, are:
Alternative Disposal Rate, MTHM/yr Reference
Mined Geologic Repository 6,000 Chapter 3
Very Deep Hole 5,000 Bechtel (1979a)
Rock Melt 5,000 Bechtel (1979a)
Island Disposal rates similar to mined
geologic repository. Ocean
transportation similar to subseabed
concept, see section 6.1. Chapter 5, and Section 6.1.4
Subseabed 5,000 Bechtel (1979a)
Ice Sheet 3,000 MITRE (1979)
Well Injection Unspecified ORNL TM 1533, DOE (1979)
Transmutation 2,000 Blomeke et al. (1980)
Space 5,000 Bechtel (1979a)
Frequently, numbers taken from the various references are rounded to an appropriate
number of significant digits in an effort to simplify this section of the document.
The general approach to each of the topical discussions used to describe the alternatives
is as follows.