organic matter, color, presence of
in two different containers.
large chunks,
gamna-spectrometry samples were
etc.).
The
The samples were transferred to a
placed in tightly sealed "tuna
disposable aluminum cake pan and
cans" made of 0.25-mm-thick alumi-
covered with aluminum foil.
num.
Holes
The large can was 3.9 cm high,
were punched in the top of the foil
8.3 cm in diameter, with a cross-
to permit evaporation.
sectional area of 53.8 em> and a
The samples were transferred to
volume of 210 cm?
preliminary drying ovens that were
was 3.3 cm high, 6.0 cm in diameter,
designed to handle about 200
with a cross-sectional area of
samples.
28.5 em” and a volume of 95 can?
These ovens were set at
The small can
a temperature of approximately
Soil-sample weights in these cans
70°C and operated contiunously.
ranged from 100 to 375 g.
The average. residence time per
samples for wet-chemistry analysis,
sample was 48 h.
each weighing approximately 50 @2,
To assure complete dryness, the
were placed in vials.
samples were placed in a second
vials was committed to chemical
oven at approximately 150°C;
analysis,
the
One of the
and the other held as a
backup sample.
sample residence time averaged
about 3h.
©
The samples were transferred
Two
to a
The gamma-spectrometry samples
were assayed for pross gamma counts
i-gal paint can and dry weights
with a 3 x 3-in. Nal (T1) detector;
were determined.
a 512-channel NaI (€T1) gamma
Sample weights
varied from 100 ¢ to 2 kg.
spectrum was measured
The samples were milled with eight
samples that exceeded 100 counts/
l-in steel grinding balls.
min.
The
for
those
‘hese preliminary Nal
(71)
sample residence time in the ball
data guided the scheduling of more
mill was between 15 to 24 hr.
precise measurements with Ge(Li)
The soil was screened
grid,
through
stainless-steel screens
produce a uniform,
2-imn
detectors and wet-chemistry proce-
to
dures.
homogeneous
More than 810 samples were processed
sample for analysis.
in the soil-preparation facility
The finely ground soil was prepared
between 4 September 1975 and 10
for gamma spectrometry and wet
October 1975 by an average working
chemistry analysis by placing it
force of 4.5 people.
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