pCi/g were found at any depth are Analysis of the sedimentand core samples indicates the presence of 410K 69 G5, 905. 10ley 102mpy 106 Ru enclosed in cross-hatched areas in Fig. 152. 127 oy Thus it seems likely that soil bearing 13T Gg 1525 154 oy 155 ny 20751, 2355 238 oy 239, 2405.) and high concentrations of plutonium — as 241 opposed to pieces of plutonium — is largely Am in some, but not necessarily all limited to a band roughly 350 m wide of the samples. across the island, centered on the visible uniformly distributed over the lagoon plutonium soil layer. floor, with the highest levels generally Within this band, Each nuclide is non- plutonium concentrations are greatest on found in the northwest part of the lagoon, the ocean side, less on the lagoon side, 2-3 km southeast of the islands ALICE and least in the island center — a finding through IRENE; the next highest levels are consistent with historical data which in- found in the area southwest of YVONNE; dicate that debris was bulldozed away and the lowest levels are found south of a from the shot point toward both shore- line extending across the lagoon from the lines after the event which produced these Southwest Passage to TOM. plutonium particles. for example, shows the distribution pat- Except for this band across the island, tern for 206... Figure 158, Similar figures have been there is no evidence which indicates thai prepared for each of the predominant plutonium particles on or near the ground Species found, puliace iu the larger area siuwnu in Wiaay Uf ihe rauionmuciides Tuund in tne Fig. 152 are also found at any significant marine sediment and core samples were depth below the surface. not detected in the water samples, in- Because of the discrete nature and random distribution cluding of these particles, of course, the only way ‘and that their distribution could be further 235 102mpy U. 106R, 1256) In only 15 samples from the northern part of the lagoon were established would be by analysis of very 155, 137 Cs large volumes of soil. 207 Bi, 8905, and 241 am detected. ang 239,240 Pu were positively identified in all samples. Radioactivity Levels in Enewetak Loe, Table 217 gives the mean surface water concentration of 137A, and 239,240 Lagoon ‘Approximately 858 samples taken from Pu in the four quadrants of the lagoon, in the ocean close to the the Enewetak lagoon environment were east side of the lagoon, and for several analyzed by germanium gamma- areas in other parts of the world for spectroscopic (GeLi) and wet-chemistry comparative purposes. techniques to determine the distribution In the plankton samples, the most abundant isotopes observed were 905. of radioactive species in the lagoon, in- (av 0.86 pCi/g, wet wt) and 7°" Bi cluding 345 sediment and bottom cores, 82 seawater and seawater filters, 21 algae, (0.83 pCi/g), followed in decreasing order plankton, or coral, and 410 fish samples. of abundance by 69 co (0.68 pCi/g), 239, 24054 (0.39 pCi/g), 195 Ey (0,24 pci/g), 741 Am (0.23 pCi/g), and '3"cs Figure 157 shows the major sampling locations for this marine program, II-8