2.4.3
Program 35, Radfobiolugical Survey
Objectives were to measure the amount and distribution © radioactive
materials in the fauna and flore on the islands and waters of the PPG and
adjacent areas.
1. Pre-test surveys were conducted to determine the level of
residual contamination from previous test programs.
2. During the period June lt to 2f, 1956, a marine survey operating on the USS Walton (DE-361) measured the yradiation in plankton, water,
and fislr samples. Fifty-three stations in the area between 11° to 14°N and
159" to 166°H were covered during the 3c00-mile cruise.
A continuous ree-
ord of the radiation in the surface water was obtained with a probe. Plankton samples from oblique tows to a depth of 200 meters and water samplics
from the surface, 25, 50, 75, and 100 meters, indicated radioactivity at each
station. Highest radiation readings in olankton and water aamples were from
stations north of Bikini Atoll, Radiation decreased im amounts around the
edge of the survey areca.
3. Algae have been collected on the reefs of Eniwetok and the
level ef radiatice, especially the short-lived taaterials such as J-131 deter-
mined.
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4. Plankton samples from the decp passage at Eniwetuk were
obtained on a three-times-a-week schedule. Suck samples should be useful
in evaluating the drift of radivactive material from Bikfhi,
5. Foods of the native people of Wotho, Tarawa, Kusaie, Ponape
and Ujelang were monitored.
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6.
Residual radiation in the soil, water, and foods of Rongelap
Atoll is being evaluated prior to the return of the native people.
7. Post-test surveys wil: be conducted of biological contamination
and the movement of radioactive material around and out of Enlwetok Lagoon.
8. Rat populations on Engebf will be studied to evaluate numbers
of survivors, level of food contamination, and emount and kind of radiation In
various tissues of the residual population.
9. Post-test survey of Bikini Atoll will be conducted.
10. An oceanic survey will start on September 1, 1956, at the
eastern cdge of the mass of radioactive water and proceed to the western
edge of the contaminated water mass.
This survey will be similar to the
one conducted June 11 to 21, 1956, but will extend farther to the west.
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