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fractionation between the whole and prepared sample is made.
The data
resulting from these analyses were used with three goals in mind, as stated
in Section 4.1-1.
The first was to optimize the sediment sample size for the
plutonium analysis.
This goal was simply met as described in Section 4.1-]
and proved entirely satisfactory.
Second, an attempt was made to estimate the accuracy of the rapid technique by comparing the total alpha concentrations with concentrations obtained
by conventional techniques.
The data shows that the simple technique developed
to estimate the total alpha radioactivity of the Bikini sediments provided
concentration data which is within about 11% of the concentrations estimated
when the counting data are subjected to a more accurate but time-consuming
treatment.
The more accurate treatment requires a knowledge of the range of
the alpha particles present in the sample.
Since this requires either a
knowledge of the relative proportions of the alpha emitting radionuclides
present, the rapid method
employed
only "survey" results are needed.
represents a considerable time-saving if
The concentration data generated by either
the rapid or conventional treatments was compared to the alpha radioactivity
obtained by summing the concentrations of 23942405 2385. 24 an, and the
alpha emitting members of the 238) decay chain measured directly and/or estimated in the samples.
These comparisons show only approximate agreement.
Some of the concentrations obtained by the total alpha technique also give
impossibly low or high concentrations.
This probably resulted because of
inhomogeniety of the radionuclides in the milligram sized aliquots measured by
the total alpha method.
Because of this and other uncertainties discussed in
Appendix I, further comparisons of the alpha radioactivity measured by direct
Spectrometric and the rapid technique were abandoned.
If pursued, the sample
inhomogeniety problem could be minimized by replicate analysis to provide more