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

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Reasonable bounds for these rates can be formulated with data now in We hope these comments will be helpful to you In the preparation of a
hand from the geologic record, but a research effort to do so should final statement.
be put in place. Sincerel
The discussion in the EIS uses the probabilities for faulting and
fracturing interchangeably, but they will not necessarily be the same.
Clairborne and Gera (1974) treated the problem of major fault development S cial A"Stltat to
across the repository. Fracturing could be induced by distant seismic
events or by the presence of the repository itself. Whether fractures -slst r SECRETARY
can remain open in salt long enough for transport to take place remains
an open question that needs emphasis in the EIS. Attachment
Values for southeast New Mexico should not be used in a generic statement.
Certainly, faulting rates of 102/yr, typical of the San Andreas system,
could be avoided. A reasonable, "conservative" upper bound for this
analysis might be lO- 4 /yr. The discussion on page 3.1.156 would then
conclude that the risk from repository breach by faulting and flooding
would be no greater than the risk from lightning, assuming the rest of
the analysis is correct--not definitely seven orders of magnitude less.
Another possible effect of geologic storage of radioactive wastes is
the increase in underground pressure as a result of entrapment of gases
(helium, radon, etc.) released through radioactive decay schemes. This
increased pressure, if not properly relieved, could lead to the development
or reopening of fissures that would result in the escape of
radioactive materials to the surface. The final statement should address
this potential event.
Decision grid
The use of the decision grid approach may be premature and unjustified
at this stage. It invites invalid, quantitative comparisons of options
to be made. Even though the report warns against this, there will
always be those readers who tend to seize the numbers and use them
improperly. Other concerns with the decision grid approach are also
expressed in the attachment.
Other options
Other options such as seabed disposal and deep-well disposal also have
to be considered promising for the future and should be pursued simultaneously
with conventional geologic disposal. If properly pursued, one
of the other options may eventually prove to be superior to conventional
mined repositories, in which case it should be adopted. This need for
continued pursuit of other technologies should be more heavily stressed
in the final statement.