In addition to receiving fallout while at Bikini and Enewetak, the SIOUX was
utilized to "map out" the over-water extent of the fallout following Shots YANKEE
and NECTAR.
While aiding in this experiment (Project 2.7), the SIOUX was required
to steam through water contaminated by fallout and take periodic water samples and
sea surface intensity readings.
The ship's path through contaminated water and water
intensity readings are well documented for a five day period following Shot YANKEE
(Reference 13) and it is possible to reconstuct the radiation environment to which the
crew was exposed while participating in this experiment. Similar documentation is not
as complete following Shot NECTAR since the USS MOLALA (ATF-106) served as the
primary water sampling platform during this experiment.
The few intensity readings
obtained from the SIOUX indicate the ship was in water much less contaminated than
it was after Shot YANKEE (Reference 13). The resultant crew exposure would thus be
much less.
Figure 2-32 depicts the reconstructed radiation intensity of the water through
which the SIOUX steamed following Shot YANKEE.
Several simultaneous measure-
ments made on the deck of the ship indicated deck level (topside) intensities due to
"shine" from the contaminated water were approximately 40 percent of the measured
water intensities.
Prior to its Project 2.7 activities during May, the SIOUX was in and out of Bikini
Lagoon on nine occasions between 6 March and 17 April.
Integrated intensities due to
hull
determined
contamination
while
contamination model.
in
the
lagoon
have
been
from
the
These are detailed below for each period in and out of the
lagoon.
Time at Bikini Lagoon
Month
March
ship
In
06/1726-09/1316
11/2102-12/0456
13/0810-19/0910
21/1926-22/1908
Integrated Intensity (mR)
Out
:
09/1316-11/2102
12/0456-13/0810
19/0910-21/1926
22/1908-26/0141
113
In
110.6
5.1
102.4
8.5
Out
38.7
9.5
15.8
16.7