Decay data of a Shot 1 size graded sample are presented in Table 3.3 from work done by Project 26b.12/ The rate of decay of all fractions is the same for all but one fraction at times from 5 to 30 days after the shot. The absolute value of the decay exponent de= creased at later times but the smaller fractions exhibited relatively higher rates of ddcaye 30302 Shot 2 The Shot 2 decay=curve slopes,as plotted on log-log paper, increased with time when the time scale was based upon Shot 2. This phenomenon is unlike fission decay either with or without uranium capture products. The curves as plotted on a Shot 1 zero-time scale appear to be normal fission decay. The activity collected during the Shot 2 sampling period could have come from contamination already on the ground around the collectors either by the action of winds, shock wave,yor by contamination which was displaced from the Shot 1 crater by the Shot 2 detonation. Undoubtedly, some contamination caused by . the Shot 2 detonation fell on some Bikini land areas. However, in the few determinations mde, the total amunt of fallout activity on the islands was too smll to mterially affect the decay rate attributable to Shot 1. The decay of Shot 2 samples can be represented by: AS A,(t #623) A = Activity at any where A,= Activity when (3.13) time t = 1 t = Time in hours after Shot 2 623 = The time in hours between Shots 1 and 2 n = The decay exponent Shot 2 decays are presented in Table 3.4. The data from one sample plotted to both Shot 1 and 2 times are shown in Fige 3.36 The Shot 2 average decay exponent is about -1.4 between 600 and 1200 hr and about 1.25 between 1500 and 4000 hr. These values are in fairly good agreement with Shot 1 values. Because of the paucity of Shot 2 decay data, the Shot 2 activities were corrected to sampling time by the use of the Shot 1 composite decey curve described in the preceding section. 32303 Shot 3 Extrapolation of most Shot 3 acti lesyas similar to that of Shot 1 activities. The activity due to U“37, 0°97, and Np*39, respectively, can be represented bys Ag = Ago(020007e70-00431t £ @-1-77% 4 0.0065200°74) (3,24)