SLIDE 36 PROTRACTED PHASE INTRODUCTION Subsequent to World War II, persons from the United States carried out several series of atmospheric tests of nuclear weapons in the Northern Marshall Islands between the years 1946 and 1958. Om March 1, 1954 at Bikini Atoll, BRAVO, the first of six nuclear-weapons tests in the Castle series, was detonated. Due to an unanticipated wind shift, the BRAVO device produced substantial surface contamination on the inhabited atolls, Rongelap and Utirik. The Utirik and Rongelap inhabitants were returned to their home atoll in June 1954 and in June 1957, respectively. The earlier repatriation of Utirik Atoll was based on the low measured level of external radiation exposure over a three-month observation period. The Utirik population was subsequently examined by a Brookhaven medical team during 1957; 144 people received comprehensive physical examinations. In 1957, the Rongelap inhabitants were returned to their atoll to occupy new homes, community structures and other facilities which had been constructed during their three-year stay at Majuro and Kwajalein Atolls. During the first few weeks after the accident and at least once every year from 1957 to the present, a Brookhaven National Laboratory (BNL) medical team, organized by the Atomic Energy Commission (and its successor organizations) and the Department of Defense, has regularly conducted medical examinations to monitor the health and to evaluate the radiobiologial status of persons affected by tropospheric fallout from the BRAVO nuclear test. Reports of their findings, including whole-body counting data and urine activty concentration data, are available in Cr56, Du56, Du57, Wo59, Co56, Co58, Co59, Co60, Co62, Co63, Co65, Co67, Co70, Co75 and Co8Qa. These reports may be consulted in order to follow the information presented here. Estimates of the intial body burdens of internal emitters were presented in C055, Coh56 and Coh60. Since April 1978, the bioassay program and whole-body counting studies have been performed by members of the Safety and Environmental Protection Divison of BNL. Reports of their findings may be found in Gr/7/7a, Gr77b, Le80a, Le80b, Le84, Mi80, Mi81 and Na80. In addition to accidental contamination of people, certain groups of people were moved off their lands to prevent potential contamination which would result from the testing Program. Bikini Atoll was one area used to test nuclear weapons from 1946 to 1958. Prior to commencement of the testing program, all Bikini Atoll inhabitants were moved first to Rongerik Atoll and then finally to Kili Island. Cleanup efforts at Bikini Atoll began in 1969 and persons decided to reside on Bikini Island at that time. By April 1978, the population numbered 138 people and consisted of caretakers and agriculturalists plus other Bikini families who found their way back via trade ships. This population remained on Bikini Island until they were relocated in August 1978 to Kili Island in the southern Marshalls and to Ejit Island, Majuro Atoll. 38