TABLE 4.7—Beta-Gamma Data on Water from Rongelap and Utirik
(66 Days Postdetonation)
Amount of
Sample
sample (cc)
Jon chamber
Rdgs (mv)
Beta activity
(Sr® equivalent)
(uc)
Beta to gamma
ratio (uc/my)
Rongelap Water
Well solids
Well filtrate
800
Cistern solids
Cistern filtrate
800
0.042
0.09
2.1
0.011
0.04
3.6
0.053
0.13
0.067
0.10
1.5
0.180
0.247
0.62
0.72
3.4
0.002
0.005
0.002
0.006
1.0
1.2
0.007
0.008
0.029
0.02
0.7
0.041
0.15
3.7
0.070
0.17
Utirik Water
Well solids
Well filtrate
600
Cistern solids
Cistern filtrate
800
TABLE 4.8—-Distribution of Beta Activity Among Various Size
Rongelap Earth Particles
Diameter range
q)
Weight of
fraction
(g)
Total
weight (%)
Beta activity
(uc Araction)
Beta activity
(percentage of
total activity)
>1650
833-1650
416 —833
208 —416
< 208
148.9
15.3
42.6
121.2
5.8
44.6
4.5
12.7
36.3
1.7
0.89
0.33
1.20
18.10
6.46
3.3
1.2
4.4
66.7
23.9
Absorption measurements made on the earth samples gave the results listed below.
Particle-size range
Ty
Percentage
800-1600
104 mg Al/cm?
38 mg Al/cm?
37
43
7 mg Al/cm?
400-800
92 mg Al/cm?
26 mg Al/cm?
20
54
35
(Remaining fraction very soft)
The activity associated with earth samples had about equal amounts of a hard and a medium
component, in addition to a very soft component.
46