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