The design of small mammal studies should receive careful considerations at the nuclear sites. The designs presently in use at the
safety-shot areas yield data that are difficult to relate to soil and
vegetation concentrations.
These difficulties arise primarily from
the mobile nature of the animals and the lack of detailed knowledge
relative to the levels of contamination to which individuals are
exposed.
Explaining the variability observed among animals captured
at the same trap location is, therefore, a difficult task.
The procedures used to prepare soil before being sent out to the
laboratories for analysis need careful review before sampling begins
at the nuclear sites.
The practice of sending ball-milled samples to
some laboratories and sieved
(after ball-milling)
samples to other
laboratories (the case for TTR and Area 11 soil samples) has created
problems of the comparability of soil results between laboratories.
Hence,
this practice should not be continued for the nuclear sites.
All aliquots of soil leaving the soils preparatory lab should be
prepared in the same way, regardless of which analytical laboratory
is to receive the aliquot for analysis.
Furthermore,
the recommended
procedure is to ball-mill but not to sieve the soil samples.
This
recommendation is based on data from the safety-shot sites that
suggest concentrations in sieved soil aliquots are greater than those
in unsieved (but still ball-milled) aliquots.
This effect would
presumably also be present for soils at nuclear sites.
EXPERIMENTAL CLEAN-UP PLOTS
Plans are being made to establish small experimental clean-up plots
on nuclear and/or safety-shot sites for purposes of choosing among
several clean-up procedures on the basis of cost, effectiveness, and
posttreatment stabilization of the areas.
The design and layout of
these plots will require particular attention to the specification of
detailed objectives, variables to be measured, kinds of field and
laboratory instrumentation to be used, control (if possible) of cross
contamination of the treatment plot from the contaminated sites, and
the selection of the sampling and experimental design.
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The placement