Fission yield curves have been determined for various fission ns detonated to date. Although some suck information exists for the fusion-fission cevice detonated at IVT, it was necessary to deter~- the important radionuclides produced by the detonation of new types of. devices at CASTLE. . The presence of activities induced in elements found in sea @ater was reported for Shot Baker at CROSSROADS. An analysis for induced qotivities was also nade at JANGLE.19,4/ It was shown that the single Ane rtant induced activity present in JaNGLE fallout any time during first 90 deys after detontion was Np23?, formed from 0-93 present ‘gn the device, No important induced activities have been reported for VY. However, some unconfirmed data indicated an activity present in pigh yield at early times .42/ Detonation of certain of the CASTLE devices ower water posed the question of the extent to which importent induced activities woule be formed under these conditions. : Calculations for estimating the contribution of different chenieal elements to the rate of gamma radiation have been made. Yields from glow neutron fission were used. Data regarding the number end energy of the gamma reys emitted by various radionuclides were incomplete, To Aimprove the validity of these important calculations better radionuclide yield data were required. Also it was important to mensure the gamma energies of a few radionuclides, ®or which the energies had not been edequately defined. It has been shown that contamination-decontamination behavior 4s a function of the physical and chemical properties of the conteminent system. This is illustreted by the ease with which gross particulate contaminants are removed poetby the relation of particle size to decontamination efficiency ,18/and by the influence which comnogition end oxidation state of liquid contaminants exert on deccntamination effec- tiveness.22)23,24,10/ Definition of the real conteminant system was therefore an important prerequisite for specificaticn of contaminant. simulants, Definition of any chemical system requires « knowledge of the identity and amounts of its various components. The contaminating fallout from each shot consists largely of nonradioactive materials. The production of realistic laboratory contaminants for more basic infornetion about radiological decontamination has, in the past, suffered severely from the absence of elementary information about the actual contemination-decontamination system in question. Since real conteni- nation had not been weilable, many investigations were conducted using highly questionable contamination procedures with no available means of relating the data to real events. Knowledge of the concentrations of BaAcro constituents along with radiochemical analytical data provide all the information neeced to orepare laboratory contaminants which would consistently have the same reneral decontaminetion characteristics. With such added information as field isodose data in conjunction with {soconcentration plots from these data, laboratory experiments on the effect of level on decentamination can he investigated ~zliably. The thermodynamic states of inactive or bulk materials usually are of greater importance than those of the redioactive constituents. It is inconceiveble, for any radiological contamination of interest, 17