arod
ane
ZR2NE
wt
<
JY
_
-s
several
mia
minctes.
raule
presents
1
at various
+
TON
sae
OF
MOTO
the means
locations
mee yn ene an
ot
LASCaAnTanoco.s
(tlo}
ow ae
tiw
es
YTesulnss
canon
orf exposure
in Micronesia.
Soil
5
oo
rate measurements
samples
(Table
2)
from these areas were analyred for gamma-emitting radionuclides
ton,
Erooknaven
Laboratory for Radiation
National Laboratory.
The
vertical distribution of fallout nuclides in the soil was
cetermined Sy vertical sampling profiles to a depth of 50 cn.
- concentrations of
’
'*?’Cs
tended to decrease exponentially
with depth, with a "relaxation length
tr
of about 3 cm?g7!.
cepositions of '?7Cs were calculated by integration
Areal
of the depth
cistriduticn determined from the vertical sampling profiles.
Exposure rates were then calculated by applying the coefficient
for 177Cs at 4.8 cm*g”! from EML-578 (8).
These samples were
also analycted for “°K and for the uranium and thorium chains
zor which the vertical profile data were averaged at each sample
location.
Tne respective exposure rate contributions were calcul-
ated from coefficients in HASL-195 (9).
tion was
assumed to be
3.2 vR/hr.
The cosmic ray contribu-
(10).
Attempts were made to reconstruct ambient background exposure
rates
from soil analyses and the cosmic ray contribution at
Majuro,
Ponape and Truk.
+ and 5.
These locations are sufficiently distant
irom the test sites
Marshalls,
These data are presented in Tables
that
3,
(> 500 km)
(Bikini and Enewetak Atolls in the norther.
no evidence could be
found
to sugsest
that
they