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 0°, 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 LL p sieve were centrifuged, washed with approximately 20 ml of acetone, and dried. They were combined with the fraction velow ho » 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 20 ay? 3.4.2 n zo Preparation of Samples The vartous fractions of the size-graded fallout were weiched, dissolved in 5 ml of cone, nitric acid, and heated to insure complete dissolution, Aliquots of the aqueous phases were fumed to dryness twice with concentrated nitrie 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 " mannere For the leaching studies a weighed quantity of the solid fallout was placed in a sintered glass crucible ond slurried with 10 ml of water for 10 ming The mixture was filtered through the eructble and the filtrate diluted to volume, The crucible was dried at 110 C for 30 min, cooled, and weighed ta detervina the weicht cf sample removed vy the leaching, Subsequent leaches were carried out with dilute hydrochloric acid which permitted greater dissolution of the particles, 303 Radiochemistry us ya" ang vo? analyses wpre performed at the test site; Ca°’, Fe°?, sr ?, Zr? ? Balko, and Cel44 analyses were performed at the Army Chemical Center, Four aliquots of eagh sample were taken for each analysis except in the case of the Nac one aliquot was analyzed, procedure where only The reported results are the averages of the four aliquots, The separation procedure fur sz®9 and galbO 45 essentially that of Slerndenin, 11/ The only sipificant modification is that the barium is finally precipitated and procedures for zr, HoP?, and C mounted as the chromate, The are the methods employed by the Zagiochentstry Group J=11, Los Alamos Scientific Laboratory. i The ta24 and Cal analyses were developed by these Laboratories and 23 SECRET —- RESTRICTED DATA are