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SUMMARY
1.
A survey of the radiosctivity in the
sea water,
plankton
and fish was mede in September 1956 in an area bounded by g° x
and 15° N and aprroximetely 145° E and 166° £.
2.
The general pattern of distribution of activity in the sea
showe a sharp decre&sse in activity east of Bikini and a gradual
Dut irreguler decretse west of Eniwetok.
3.
Plankton appeers to be the most sensitive
readizactivity
in the
sea;
the
indicator of
average of ratios of plankton
activity to sea water ectivity was 2,500.
4,
od
:
The highest value of radioactivity in plankton, 21,000 d/m/g
wet, wes found about 80 miles north of Fniwetok and the lowest
velue, 27 d/m/g, near Guan.
5.
The highest value for water activity, 19,009 d/m/l, was
found between Eniwetok and Ujelang and the lowest value, 48
a/m/l. northeast of Bikini.
6.
Sea. water filtered through millipore filters had higher
devels of activity than the residue on the filter paper.
7.
Microplankton is probably the principal source of the
radioactive particulate metter.
8.
POE ARCHI
VES
The change of relative radioactivity of the water with
depth is variable but appears to fall into regional patterns.
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