The deposition of Strontium-90 may be described
In two ways:
one
Is
the rete of fallout, usually on the
basts of monthly collections and the other Is the cumulative deposition based on sot!
analyses.
These
two methods
ere considered supplementary since none of the monthly pot
collections were started eerly enough to allow valid estimates of the accumulated deposit.
On the other hand,
difficulties in the sampling and analysis of solls prevent
use of soll
deta
for
short
term rate measurements,
Monthly Collection Networks
Monthly collections of fallout have been made
for a perlod of several yeers using stainiess steel pots,
The network reporting results for
The stations
are also
listed
1958 Is mapped in Fig.
in Table
|.
1,
fn order to expand the collecting network, an
Improved device consisting of a plastic funnel and
exchange column hes been developed.
ion
Through the coopera-
tion of Dr. Lester Machta of fhe U. S$. Weather Bureau, an
additional) 22 sites were put
of 1959,
into operation
in February
These are shown superimposed on the pot network
Ia Fig. 2, and listed tn Table 2,
way to further expand the funnel
Negotiations are under
network outside the
United States and fo substitute funnels for existing pots.
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