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~hDr. Gustafson reported that the radiological resurvey of Bikini Atoll
consisted of taking numerous radiation exposure measurements, and collecting
representative samples of the prominent plant and animal species (including
fish and birds).
Particular efforts were made to sample those items likely
to be consumed as food by the returning Bikinians.
were used to measure radiation dose rate.
Several kinds of devices
Confirmation of dose rate by more
than one instrument increased reliability, and the field y-ray spectrometry
provided detailed information on the radionuclide composition of the
contamination.
The island of Bikini was surveyed most extensively.
The former village
was located here, and remains the most desirable location for permanent
housing.
The beach area, village site, and selected transects across the
middle and both ends of the island were surveyed for radiation levels.
The
dose rate at or near the beaches was lowest due to leaching and wash off of
radioactivity.
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(7 10uR/hour).
Radiation levels were comparable to those found in the U. 5S.
Higher levels (roughly twice to three times beach values)
were present in the interior (densely overgrown) regions with some hot spots.
A sizable area was cleared of vegetation, and dose rates remained essentially
constant.
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vegetation.
Other measurements indicated radioactivity to be present in the
Hence one may conclude that as the shielding effect of plant
material is removed, the dose from ground deposition compensates for the
removal of radioactivity in plant material.
Under habitation, the islands
would be cleared of underbrush; hence, the plant source will be removed.
Plowing under, or otherwise burying the top layers (inch or so) of soil