field was determined from experimentation in the laboratory
with "spiked" sea water samples and in general vas a double
precipitation process in which most fission products were
brought down in a ferric hydroxide scavenge.
strontium vere precipitated as oxalates.
Calcium and
The specific pro-
cedures are outlined in the Appendix.
Results.
Results are presented in Table 1.
It is to
be noted that the values in this table are in terms of milliliters of water sample and that the disintegration rate {is
as stated and not in thousands as has been used in other
tables in this report.
scavenge"
Also the values for both the “Fe (0H);
and the "“Ca-Sr oxalate”, even though small, have
considerable reliability because the values have been based
on large samples.
The total sample activity was divided by
the number of milliliters in the sample, which was 6,000 for
the pre-test samples and 500 for the post test samples.
The
values for “whole sample" (post shot) were based on a 3-milliliter sample that was withdrawn before precipitation and hence
would be expected to be less reliable.
From inspection of Table 1 the following conclusions can
be drawn.
For the pre-test samples radioactivity of the
Bogombogo sample was considerably greater than for other
stations.
Why it was greater is not known, but activity of
plankton samples was also greatest from this station.
There
were small but measurable amounts of activity in water samples
from other stations.
For the post test samples the amount of
activity in the samples was closely and inversely related to
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