os ae) pe oe EE nN | a ateveweit ceei - teva: gobs our we ee - oe cee eat ee em tera oS - only the activities of the major isotopes present but also. their depth distribution. We found that in high activity areas most of the activity (2 or more) was usually in the top 2 to 3 inches of soil. =~ Because of the large local : : variations in soil activity on all the islands it was not ~ “~ . possible to calculate accurate exposure rates in air from : , : a the one or two soil samples obtained per site. * iearest ~~": Fe; Inasmuch as +5 ais * an oN + * = the field spectrometer and ionization chamber "see" large * areas . . . - ~~apa _. eo (~30 feet in diameter), they everage out the local .. . variations giving very reliable absoiute exposure rates. . ; tee The soil samples proved very useful, however, <or identifying ' rin f° and determining relative activities of the isotopes present _ & Which were then usea to estimate the relative contributions . of these isotopes to the exposure rates at the various i sites E. the same sites with the spectrometer-ionization chamber (3). m The relative exposure rate values obtained for oe ~~ \ system and from soil sample analysis agreed: quite well. ' : * aeAoae | es co OG The composition of the radiation field determined from ~*:: . - EM el ae w= e = eo moe agib om. * “tHe soil samples and field spectrometry for low and inter- # , : -... . mediate fallout areas aifterea considerably from thator rae ¥ oe blast areas. re a “eat* ee wot eit eam ge ~ a-U ae ~ ad? , .- ss TheBich contribution to ‘the exposure rate os Leo ee am tg meneewe eens ogee kaye eee (fei ieee eh _ a tee em coe war ce . . ” ea - eo so cage i + he += I . Bee ee tye ee te eee cw T = “eewee ree aRANANTae ar 2 et ae tiem erga . nee kee oot eterna wee te yee . roege wo ee 4 . ee oe =_ -_ = . - x - eee —_. 7m a oe ” b . - oe