small.

No samples suitable for particle analysis were obtained from

Shot 3.

Followiny Shot 1, 6971 radioactive particles were analyzed from

the area within the Bikini Atcll and 621 particles collected on the outer
atolls of Ailinginac, Rongelan, and Utirik were eveluated. The differential fallout collector on the island of Alice contained some particulate from Shot 6, These data are also presented.

5.2.1

Shot 1, Close-in Faliout

The size distribution of close-in fallout particles with resnect
to time for four lagoon and thrae island stations are given in Apnendix

C.

Only radioactive particles ave inciuded in the date.

Of the 40

available sampling increments within each differential collector, those
increments that visually appeared to contain a large amount of particulate were selected for analysis, Increments over a wide time period
were likewise selected. Analysis of the bar gravhs with resrect to
rate of arrival or time of arrival is therefore an approximation. Data
on tine of arrival are presented in Section 5.6 of this report.

Figire 5.4 shows the gsiza frequency distribution of the Shot 1
close-in particulate. It is a comsosite of the bar gravhs for the four

lagoon and three island stations.

(Figs. C-1 through C-7.)

Fivure 5.5 is a plot of the cumulative size distribution of
Shot 1 particulote presented en a lop probability eraph. The size
distribution is very close to log normal with u geometric mean particle
diameter of 112 p
5e2e2

§=Shot 1, Cuter Island Fallout

Satples of earth were collected ty the outer island survey veam
following Shot 1.15/ The radioactive varticulste found in these scil

samrles was analyzed for size distritution and the recults are presented

in Fir. 5.6.

These atolls were 70 to 2°0 nautical miles from Shot 1.

Firure 5.7 shows a loz normal] size distrittion for particles collected
on three atolls. ‘The raometric meen particle diareters are presented

in Table ©.A.

TasL™ 5,4 - Geometric Mean Particle Diareter
Atoll

f

"

Bikind

|

Ad linginae

|

Reagelon

L

Utirik

| Distcncee from! Geonetric Mean
Shot Point |farticle Dieareter

(n mi)

(u)

|

10

112

|

70

£9

107
‘

277

[
59

70
/,

°

:

'

Select target paragraph3