114 contaminated sediments presently found in this area. Seteatetate : One of the most dominant aspects of the distributions of the several radionuclides measured are the differences between them. of high 239+240 Pu, 24) An, 155 Eu and 137 The major distributions Cs concentrations, which are located in northwest quadrant surface sediments, differ greatly from the distributions of 238 bu 2075; and 60%, whose highest concentrations were found in crater sediments. A great deal of the differences found can reasonably be attributed to the difference in the source terms, each of which contributed varying quantities of debris to the different locations in the lagoon. In that one of the most interesting aspects, relative to the marine chemistries and environmental fractionation of the different radionuclides, may be their different spatial distributions, it is unfortunate that the complexity of the multisource term introduction of the radioactivity appears to prohibit comparisons to be made of the distributions from individual source terms. A great deal of the ambiguity which prohibits comparisons to be made arises from the mixing of debris produced by the Zuni and the Station B-18 area tests. Within the region of the lagoon encompassed by stations B-18, C-8, B-19, B-20, B-22 and B-24, the distributions of ~°’Bi, 207 i; 6 ©°co and S5ey differ not only from each other, but also from the fairly constant proportions in which they occur (compared to 23942405.) in the eastern, central and northeastern lagoon. Except for 13766 the fairly constant ratios of the radionuclides to 23942405, in the central lagoon can be interpreted as evidence of a low degree of chemically related fractionation between the several radionuclides in the debris depositied here. It is clear that without the ability to demonstrate either the initial or present radiochemical composition of the source terms to the various stations sampled in the lagoon, investigations of the extent to which various