3. Rationale for Current DOE Environmental Programs in the Marshall Islands The basic rationale for current DOE environmental monitoring research and dose assessment programs in the Marshall Islands is to develop a reliable data base for estimating radiological doses to populations on the northern atolls. This data bdse also provides a basis for information on resettlement options at Bikini and Enewetak Atolls and provides the necessary basic research data to allow predictions of dose beyond one point in time. The data for the various parameters in the dose models are available as a range of values; a mean value for each of the parameters is determined from the available data. As a result, the average dose calculated from these parameters will represent a range of doses determined by the distribution of the data for each of the model parameters. Therefore, it is possible for a person to receive a dose which exceeds the average dose and for this reason it is essential to develop monitoring and research programs to refine the data base for making tnese dose assessments. Programs conducted at the atolls prior to 1968 were not directed toward developing dose assessment capabilities. The programs had limited and specific goals, more of general academic interest, and were not directed toward providing an adequate data base upon which predictive dose assessments could be made. The surveys conducted at Enewetak in 1972-1973 and Bikini in 1975 and 1978 were the first large scale efforts designed for this purpose. As a result of performing the dose assessments from the data generated in these surveys, it was possible to : (1) define the data required to improve the dose assessments (2) define areas of research which would delineate radionuclide cycling mechanisms in the atoll ecosystems, and (3) define experiments to evaluate methods of reducing either uptake of radionuclide into subsistence crops or the soil radionuclide inventory. 10