2.
A method has been proposed of producing,
in situ, by thermal
and mechanical means, relatively insoluble iron-rich silica
compounds like those which appear as natural end products of
soil and rock weathering in certain parts of the world.
This
would require the Pu-contaminated surface layers to be picked
up,
fired to temperatures sufficient to fuse iron-silica mixes
which would carry the Pu into inert, chemically inactive
compounds, thereby effectively removing Pu from wind, weathering,
and biotic processes.
This would likely be expensive, disruption
of the environment would be complete, and recovery would be
uncertain.
3.
Leaving the Pu on the soil and rendering the soil surface
immobile by surface agglomeration and fixation or by covering
with a macadam or concrete surface,
from biotic processes,
also intended to remove Pu
has been proposed.
All these proposals have certain characteristics in common.
Their
objectives are to remove Pu from contact with biotic cycles, and
from the further widespread distribution by wind and water.
Most
of the proposed methods would require extensive disturbance of the
areas.
Some would also present the hazard of contributing to
further distribution of the element, even if on a short term, and
some would leave earth surfaces denuded of native vegetation and
subject to severe erosional processes on whatever Pu may have been
left subsequent to the operation.
All proposals are based on the
hypothesis that Pu in the field in its present state under present
conditions is a hazard which should be eliminated or at least
properly mitigated.
There is a concomitant with this position paper, a solicitation of
proposals for pilot projects to undertake cleanup of Pu-contaminated
areas and other areas contaminated with other nuclear debris.
No
doubt there will be other methods proposed or combinations of the
above-suggested methods.
This paper is a response to that solicita-
tion for proposals, but supports,
instead, the hypotheses that
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