CHAPTER 2 EXPERIMENT DESIGN Chemical, physical, and rediochemical neasuremente were nade on the fallout samples collected at lagoon, island, and sea stations. Short lived radinactive species were analyzed in the forward area; the remainder of the analyses were made at U.S. Naval Radiological Defense Laborstory. Owing to many unforeseen difficulties early samples for the rediochemical analyses were not obtained, although early decay data were obtained from several shots. The number of samples collected was much smaller than planned. However, it was possible to get considerable information concerning 911 planned phases except those involving very short lived radioisotopes. 2.1 DETERMINATIONS UNDERTAKEN To investigate the chemical, physical, and radiochemical properties cf the fallout the following determinations were undertaken: a, Amounts of radioactivity in soluble (ionic), colloidal, and insoluble fractions. b. Concentration of macro constituents, primarily the elements which occur naturally in coral and sea water, but also the elements present in large amounts in the weapon assembly and associated equipmente c. Oxidation state of certain radionuclides whose final state under the conditions of the detonation could not be predicted, and whose contamination-decontamination behavior is believed to depend upon their oxidation state. d. Size distributions of fallout drope and particles, and the variation of these distributions throughout the sampling array. 6. Specific radioactivities and salt content of various particle and drop size fractions in fallout. f. Chemical and crystalline composition of individusl particles. g. Size distributions and presence of radioactivity in both liquid and dry aerosol particles; presence of salt ir liquid aerosol particles. h. Radiochemical composition of fallout, especially determination of the fission yield curve and the degree cf chemical fractionation among the fission products. 19