-9- ( ‘. ;,, . . ,. I 1 1 I I I II I I I Ill I I I 1 I 25 . 20 15 10 (- 5 0.1 0.5 1 5 10 50 Particle aerodynamicdiameter,pm Figure 2. Plutonium activity (pCi g-l) versus particle aerodynamic diameter D (pm) at the 1.1 m height over bare soil on Bikini Island (wind speed 4.5 m S-l, surface contamination 15.3 pCi g-l). ● * (., . .