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Part Vill
Biology and Medicine
RADIOBIOLOGICAL SURVEYS IN THE PACIFIC QED)
Preliminary results of some of the radiobiological surveys conducted in the Pacific during
the July-September quarter are given below. These surveys, some of which were still in progress at the end of the quarter, were undertaken to monitor the radioactivity in the water and in
marine organisms, resulting from Operation HARDTACK. The surveys were described in detail in the Quarterly Progress Report, April—June 1958.
Fallout During Operation HARDTACK
Highly radioactive fallout was limited to the announced danger area. Radiation doses to
members of the Joint Task Force were kept to a minimum, and there were no serious radiation
situations.
Marine Radiobiological Surveys
A radiobiological survey of the danger area conducted August 9—15 indicated that the restricted area could be disestablished without hazard. A similar survey was conducted Septem-
her
in the
area
Eniwetok
and Guam,
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FY WEEE SOSEES
WAROAEg covering
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ES western
TY Oe Ok half of the
restricted area and extending a considerable distance beyond its western boundary. Sea water
and plankton samples indicated that the radioactivity levels were of the same order of magni-
tude as those found in the post-REDWING survey in 1956. Further evaluation of the results
was being made.
Tuna Sampling
By the end of Sentember samples of tuna from about 100 locations in the western and cen-
tral Pacific and 2 locations in the Indian Ocean had been sent to the Laboratory of Radiation
Biology of the University of Washington for gross beta and gamma counts and analysis. Most
of the tuna was caught in the area north of the equator, south of Japan, west of the Eniwetok
test site, and east of the Philippines. Counting of these samples revealed little radioactivity,
most of which could be accounted for by the naturally occurring radioisotope potassium 40.
a
Andmee Olen
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124-14 —
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However, at a iater time and in ALT LeUu areas, somé tuna Tsay ACQUITS BUINS FAULUALLIVILy pe
mage te
duced by the HARDTACKtest, probably by way of the food chain.
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48
Ce
ch
(Fa
Following Operation PLUMBBOB (1957) soil samples were collected for analysis for
strontium 90 from areas around the Nevada Test Site (NTS) receiving some of the heaviest
RN
oh
SOIL SAMPLING AROUND THE NEVADA TEST SITE