so that the small particles in the wash could settle through without
being blocked by large particles,
The particles remaining on the sieve were washed with approximately 20 ml. of acetone and dried, These particles were then placed
in the Roller analyzer; ail particles below 40’: in diameter were
blown over into an asbestos collection thimble, This step greatly
_ reduced the number of fines in the larger particle sizes, These
large particles were then sieved dry with mechanical shaking for 5
min into 9 size~fractions,
The small particles that had settled with the chlorobenzene
through the 4h sieve were centrifuged, washed with approximately 20
ml of acetone, and dried.
They were combined with the fraction velow
LO » that had been separated by the Roller analyzer.
(see Appendix B)
This entire sample was then separated by the Roller analyzer into 5
size-fractions,.
.
Particle sizes are reported as mean volume diameters:
dy of E04 ay? :
3044.2
Preparation of Samples
z ™
a,
The various fractions of, the size-graded fallout were weighed,
dissolved in 5 ml of conc, nitric acid, and heated to insure complete
dissolution, Aliquots of the aqueous phases were fumed to dryness
twice with concentrated nitric acid and then with a mixture of nitric
and perchloric acids, The final solutions were made up to volume
,
with water, Aliquots of all solutions were measured for gross activity
and decay, Other liquid and solid samples were treated in a similar
manners
.
For the leaching studies a weighed quantity of the solid
fallout was placed in a sintered glass crucible end slurried with 10
iL of water for 10 min, The mixture was filtered through the crucible
and the filtrate diluted to volume, The crucible was dried at 110°C
for 30 min, cooled, and wetghed to determine the wetght of sample
removed by the leaching, Subsequent leaches were carried out with
dilute hydrochloric acid which permitted greater dissolution of the
particles,
33
Radiochemistry
yar ang
M07? analyses ype performed at the test site; cal
Fe°, sro9, Zr99, BalkO, and Celli4
analyses were performed at the
Army Chemical Center, Four aliquots of eagh sample were taken for
each analysis except in the case of the Na“4
procedure where only
one aliquot was analyzed, The reported results are the
averages of the four aliquots,
The separation procedure fur cr89 and BalhO ts essentially
that of Slerdenin, 1/ The only sinificant modification is that the
barium is finally precipitated and
procedures for zr95, Yo 9, and C
mounted as the chromate,
The
are the methods empleyed by the.
Radiochemistry Group J-11, Los Alamos Scientific Laboratory, iz/ The
act and cad analyses were developed by these Laboratories and are
23
SECRET — RESTRICTED DATA
:
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