Chapter .4
ANALYSIS OF CONTAMINATED SEA WATER!
{n the previous chapter fallout dose and dose-rate contours for Shot 5 were calculated from
direct measurements of gamma activity in the sea. In this chapter dose rates are calculated for a limited number of points at which samples of contaminated sea water were collected and analyzed.
Generally, the data used here are independent of those in Chapter 3, and comparison
of results from the two sets of data provide a valuable basis for judging their reliability.
In addition, a considerable number of samples of surface sea water collected following
Shot 6 have been analyzed and dose rates calculated.
Contours were drawn, and the frac-
tions of the weapons appearing in fallout were estimated for Shots 5 and 6.
Due in large
part to the extremely short time in which this prcject was planned, executed, and samples
analyzed, sufficient supporting data were not obtained to permit accurate calculations to
be made. Nevertheless, a comprehensive treatment of the data has been given in order
to enable the reader to judge the limitations of the data as well as to outline forfuture
planning the manner in which more accurate results may be obtained.
As in Chapter 3, dose rate is calculated as though all the fallout had fallen upon a
fixed plane at mean sea level and remained undisturbed thereon.
The fallout was, in fact,
both mixed with the sea water to a variable depth and transported by current action to the
location at which it was sampled. For each point in the contaminated plane for which
data were obtained the dose rate was calculated for 3 feet above the plane by the method
of Gates and Eisenhauer (Reference 1). This method considers a source uniformly distributed upon an infinite plane. Although the actual source is not uniformly distributed, it was
! after Chapter 4 was completed some additional data became available which relate to the com-
putation of gamma dose rate and fraction of device in local fallout. Revised values of the latter
have been reported (Reference 12).
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