on every island, but emphasis was given kind of data obtained for cach of the pre- to — and proportionately larger numbers dominant isotopes on each of the islands, of samples taken on — those islands which 905. values for 0-15 cm core samples on were known to have been sites for nuclear JANET are plotted in Fig. 147, Table 215 presents geometric mean testing activity or to have been subjected to large amounts of fallout from such values and ranges for the four predominant activity. radionuclides on islands from ALICE Two types of soil samples were taken through WILMA. On islands where there on each island: "surface" and "profile." are significant differences in activity At "surface" sampling locations, two levels between densely and sparsely samples were taken— one a 30-cm? x 15- .vegetated areas, data for both are given. em-deep core, and the second a composite Similar data for groups of southern islands of two 30-cm” X 5-cm-deep cores. are shown in Table 216. At "“profile'' sampling locations, 100-cm? "Profile'' samples showed a wide range samples were taken from the side wall of activity distributions as a function of of a trench dug for the purpose. Nominal depth on different parts of the Atoll. depth increments for the profile samples amples of the types found are given in were 0 to 2, 2to 5, 5to10, 10 to15, 15 Figs. 148-151, to 25, in this area are not very meaningful, and 25 to 35 cm, and at 10-cm increments to total depth, Ex- Although generalizations Fig. 148 shows the profile distribution Total depth 1or proliie Samples varied trom 39 to normaliy touna on tne southern iStands. 185 cm, depending on the distribution ex- Here the activity levels are usually low pected from the testing history of the through the full range of depths sampled. Some sampling locations show concentra- .island being sampled. In general, the predominant species tions decreasing somewhat from the sur- found in the soil samples are 905, 137 ag face through the first 10 or 20 cmof soil. 2395, and co, 102mpy 1256p 4K, 555, lan 133, 134 4, 154 155py 207 5B: 226R 4 2385, and 241 Figure 149 shows the type of distribution 12 often found inland on islands subjected 235, to fallout but not to construction or other Am are also present in some or all of the samples. ground-zero earthmoving activities — i.e., As was the a rapid and fairly steady decrease of case for external gamma. levels, small activity levels from the surface to total amounts of radioactive species on the depth, southern islands (SAM to KEITH) are found on beaches and exposed areas on distributed-more or less uniformly over these same islands — i.e., uniform or the entire land area. slowly decreasing activity levels from On islands where Figure 150 shows the distribution larger amounts of activity are present, the surface to total depth. the highest levels of all species are found shows a distribution pattern found occasion- at the island centers or in proximity to ally on islands which have beenthe sites ground-zero sites, usually related ina for tests or have been subjected to con- direct way to the vegetation density in the struction and earthmoving activities immediate area. (primarily IRENE, JANET, PEARL, As an example of the TI-4 Figure 151