phase that included terrestrial and marine sampling; this phase had full logistics support, but was limited by the time required at each complete the external gamma aerial survey. limited sampling of the terrestrial atoll to The purposes of the associated and marine environments were to (1) supplement and provide comparative data for the aerial survey, (2) provide a preliminary evaluation of the radionuclide concentration in vegetation, soil, water, and marine foods to estimate doses from these pathways, and (3) supply sufficient information to identify islands or atolls that might require additional sampling at a later date for dose assessment purposes. The results of the NMIRS have been published (Robison et al., 198la, 1981b, 1982a; Mount, 1983; Tipton and Meibaum, 1981). in a series Noshkin et al., of reports 1981; Jennings and However, the results for Bikini Atol] were not published as part of this series. The Bikini Atoll results are published separately because, unlike the other 11 atolls or islands, Bikini Atoll was the site of 23 nuclear tests and because resettlement options at the Atoll needed to be defined. Thus, the results of the radiological survey of Bikini and Eneu Islands, the two historical residence islands at Bikini Atoll (see Fig. 2), were published separately (Robison et al., 1982b) prior to the publication of the NMIRS results, and both islands became the focus of a continuing research and monitoring program. This report is designed as a ‘resource document for the eventual cleanup of Bikini Island; it contains details on the sampling sites and number of samples collected at the islands of Bikini Atoll during the 1978 survey and the results of the radiological analyses. We have also included results of the continuing sampling program for Bikini and Eneu Islands through May 1985 for soils, through March 1987 for vegetation, and through May 1988 for rainfall. . The radiological doses estimated from these data for a population: living on Bikini or Eneu Islands can be found in Robison et al. Nearty 95% of the estimated effective dose and bone-marrow dose at the atoll results from !3/Cs; about 70 to 80% of the total dose from '37Cs arises from ingestion of '37Cs in terrestrial foods, with the remainder coming from external gamma exposure. Because of the importance of !37Cs in the overall estimated dose, and, in particular, in the food chain, a great deal of emphasis is- placed on measurements of !3/cs in vegetation and soil around the Atoll. We have developed a data base for 90Sr, 239+240py, and 24lAm as well, but it is not as extensive as that for '3/Cs because these radionuclides account for a much 2000310