RESULTS AND ANALYSIS ct exposure rate measuroments at various locations in Micronesia. Soil samples (Table 2) from these areas were analyced for gamma-emitting radionuclides ton, Laboratory for Radiation Ecolozsy (3, 7) and by Brookhaven National Laboratory. The vertical distribution of fallout nuclides in the soil was ¢@ Sy vertical sampling profiles to a depth of 50 cn. re y concentrations of '?’Cs tended to decrease exponentially boat Are réa e* with depth, with a "relaxation length" of about 5 cm?g-'. r cepositions of '47Cs were calculated by integration of the depth é tical sampling profiles. o ot cistributicn determined from the v » ™ w Q u“ rh a y Exposure rates were then calculated by applying the coefficient t 4.8 cm*g”} from EML-378 (8). eo These samples were also analyred for “°K and for the uranium and thorium chains sor wnaich the vertical profile data were averaged at each sample location. The respective exposure rate contributions were calcul- ated from coefficients in HASL-195 tion was assumed to be 5.2 ywR/hr. (9}. The cosmic ray contribu- (10). Attempts were made to reconstruct ambient background exposure rates from soil analyses and the cosmic ray contribution at fajurg, Ponape and Truk. + and 5. These locations are sufficiently distant from tna test sites Narshalls; These cata are presented in Tables (Bikini and Enawetak Atolls 53, (> 500 km) in the northern that no evidence could be found to sugysest that they