eee ou _- — anFRReC in this discussion, it has been assumed that 15% of the pon yor total residual activity of the IVY (2) MIKE detonation was teposited downwind within 30 to 50 miles of ground zero in a period of six hours. It is also believed that approximately 35% of IVY (2) MIKE fell out 1 within 12 hours, and at the end of two days 50 to 75% fall out. If this analysis is correct then a large percentage of the residual activity was deposited in the Pacific Ocean within 500 to 700 miles of ground zero, It should be noted that this analysis is primarily based upon acaling factors obtained fron W/X tower shots. 4 It may be that the extreme heights reached by the IVY (R) MIKE Cloud may reduce the downWind fall-out by as mich as a factor of 10 over that indicated above, B. ntrapment of Fission Products by Soil Debris and Water from Megaton Bambs in the Pacific It is assumed that approximately 1,000,000 tons of soil were coated with fission products and suckec into the stem and mushroom of the IVY (R) MIXES cloud. } If the ratio of inactive soil to active soil is 100 to 1 then approximately one hundred million tons of soil debris and water were thrown up during this shot. Such a vast quantity of matter upon falling hack will entrain large quantities of air, gaseous products of the explosion and fission products. It should be noted that this statement is substantiated by the fact that the Cascade Inpactors indicated a mass median diameter of 1 to 5 micron sized particles when the fall-out time indicated that particles of from 150 to 75 microns ] were falling during TUMBLER/SNAPPER (R) and UPSHOT/ENOTHOLE (R) tower shots. This means that even for the relatively small tower shots Lad f~2 i> ry yy x Cc Cri a W ' att eg UNCLASSIFIED