,. k -4- was captured, however, by an undetected stratum of wind blowing from west to east, although all the remaining winds continued to be from the east or southeast. Thus , a fraction of the fallout was transported almost due east, diffusing outward, becoming more dilute and losing its burden of radioactive particulate to the surface as it moved. The southern edge of this plume grazed Ailinginae Atoll about 90 miles east-southeast of Bikini, and the southern part passed over Rongelap and Rongerik Atolls about 120 and 160 miles, respectively, Bikini. just south of east from “By the time the plume reached Utirik Atoll some 320 miles east of Bikini, it had become diffuse and most of the fallout had taken place; Utirik therefore received only comparatively low-level contamination. numbers of people exposed, approximate Details of the time of beginning exposure to the fallout, time of evacuation from the island, and best estimate of total air dose from external gamma radiation in roentgens are given in Table I. In addition to the external dose, there was also an internal dose to the thyroid gland from radionuclides of iodine, the magnitude of which for adults was estimated with a large factor of error to have been about equal to the external gamma exposure (2). It is worth noting that the task force personnel had been evacuated from Eniwetok and Bikini Atolls into ships stationed about 30 miles to the east of Bikini on the supposedly upwind, safe side of the expected fallout pattern (l). About an hour after detonation, however, the ships’ radiation detectors began to register increasing levels of radiation and all personnel were ordered below. Rad-safe aircraft in the meanwhile had detected and charted the anomalous plume so that ships moved out of its path and after a time were decontaminated. . .. . . . .. .. .. . _=, . .- ..__ —, ..____ ...— -. -,- . -,- . . --- ..