PLUTONIUM-BEARING PARTICLES FROM FUEL REPROCESSING 141 



TABLE A.l Elemental Concentrations in Average Crustal Rock and 

 Geometric Mean Enrichment Factors of Various Aerosols 



with aluminum as the reference element and average crustal rock as the source material. 

 However, 18 particles from System I and 37 from System II contained no aluminum. 

 Thus the enrichment factors had to be based on silicon rather than on aluminum, where 



FF^Y'l = ^^/^Oparticle (Si/Al)g aerosol _ ^ -,g (^/Si)particle 



(X/Si)rock (Si/Al)rock 



(X/Si)rock 



(A.3) 



(The second set of ratios is the geometric mean of the global aerosol-crust enrichment 

 factor explained in the next section.) 



With the use of these two relationships, the enrichment factors were calculated from 

 the elemental weight percents obtained for 115 particles in System I and 156 particles in 

 System II. Six small (0.5 to 3.6 jum in diameter) iron particles in System I and two 

 particles [~15 nm in diameter and containing potassium, chromium, and iron (1 : 3 : 3)] 

 from sample point A of System II contained neither aluminum nor silicon and were thus 

 not included in the study. 



Comparative Aerosol Data 



For a comparison of the elemental composition of plutonium-bearing particles with that 

 of atmospheric aerosols, enrichment factors calculated for elements in these particles 

 were giouped according to data supplied by Rahn (1976) for aerosols. In his report 



