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

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The consequence analysis as it bears on geological repositories
If the maximum flood of record was 3 meters above the normal river appears to be too subjective. For example, the draft continually
stage, and the one in a thousand year flood would be expected to be relies on a holdup period of about 1,000 years. Yet an independent
5 meters above normal river stage, under what conditions would the study (EPA/520/4-78-00) by an Ad Hoc Panel of Earth Scientists
"maximum probable flood" which is 10 meters above normal river stage be concludes that "The containment cannot be relied upon to effect any
expected? Is this a once in a million year flood? significant (longer than 10 years) retardation of the release of the
Shigh-level waste." w:hile it is obvious that finite numbers must be
There is a short paragraph on ground water, but nothing as to the used as input for the programs employed in this appendix, the large
nature of the aquifer--permeability, hydraulic gradients, or variation possible in much of the input data suggests that
retardation factors. This should be included. incorporation of an uncertainty analysis 'and sensitivity analysis in
such calculations would permit a clearer zunderstanding of possible
134. (Appendix H) This appendix could well be omitted. Many of the consequences.
hazard indices quoted are of no value as indices, and there is no
information to enable one to select which, if any, of the indices are The criterion for public acceptability of 120 millirems per year
useful, to the maximum individual is not defensible, and population dose needs
primary consideration. If the approximately 3 million people who could
Although purporting to be a basis for determining the "hazard be supported by the river were each to receive 120 millirems per year,
index," the material as presented in the appendix does not even the population dose would be 350,000 person-rems per year or
approximate the potential hazard. The MPC is derived on the basis of approximately 70 health effects per year using the BEIR-I whole body
dose to a "critical organ" rather than on the risk related to a given estimate. Although all the postulated 3 million people would not
intake of isotope. The cumulative risk from intake of isotopes should receive the maximum individual dose and although these nuclides would
be used as the basis for deriving a comparative "hazard index" since not produce whole body doses, there is no reason to believe that the
organ sensitivities are the controlling factor as noted in ICRP 26. concentration of nuclides in the river would decrease substantially as
the nuclides moved down river.
135. (Appendix I) This appendix is deficient. It is based on leaching
of the entire repository by ground water, passage of the nuclides The analysis uses unquoted sorption equilibrium constants. These
through a rather freely flowing aquifer, and discharge into a large are probably the Battelle desert soil values which may be unreasonably
surface stream (10,000 cubic feet per second or 8.9 x 1012 liters per high. The text on page 1.6 refers to "5 miles of western U.S.
year). If we apply the generic density of population in terms of river subsoil," which is reminiscent of the Battelle "desert soil." These
flow from our forthcoming dose assessment report, which is 3.3 x 10-7 sorption constants are not necessarily typical of all soils and rocks
person years per liter, the river is capable of being a water supply and, in any case, should be listed in tabular form.
for about 3 million people, a great many of whom would receive close to
the maximum individual dose. Just as it is imprope- to neglect population dose in the river, it
is improper to neglect individual dose to users of ground water. This
There is an apparent conflict between the basic assumptions in the is completely omitted in this section. Since the ground water velocity
main text and Appendix I. The main text stated that "...disposal in is stated to be equal to one foot per day, or a little over 100 meters
salt has been emphasized..." (Page 3.1). However, the assumptions made per year, the aquifer would be expected to be a good water provider and
in Appendix I (Page I-9) for an earlier analysis (which was the basis
of the current version of the impact statement) assumed that the
repository is in a non-salt media. Furthermore, some of the details of
the model should be briefly summarized in the appendix. The statement,
"Detailed descriptions of these models are found in references 1-7"
(Page 1.4), is not sufficient. There should be a brief description of
GETOUT (Page I.10), as well.
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