The whole-body dose rates based on continuous consumption of 200 g/d of ‘fish range from 0.028 mrem/y at Mejit bone-marrow dose Rongelap. rates to about 0.1 mrem/y at the to 0.12 mrem/y at Mejit from 0.029 mrem/y range Rongelap; at The dose commitment, or 30-y integral doses, range from 0.00063 to 0.0022 rem for the whole body and from 0.00065 to 0.0032 rem for the bone marrow. INTRODUCTION A radiological survey was conducted from September through November of 1978 to assess the concentrations of persistent manmade radionuclides in the terrestrial and marine environments of 12 atolls and 2 islands in the Northern Islands. Marshall Likiep, Taka, The atolls Ailinginae, and Wotho, islands Bikar, are Ailuk, Mejit, Jemo, Rongelap, Bikini, and Enewetak. on specific shown in Fig. Rongerik, 1 and include Ujelang, Utirik, Concentrations of radionuclides islands of Bikini Atoll have been well documented. !~* However, little radiological information is available for the remainder of the atoll or for other atolls that were considered most likely to have received fallout from nuclear tests conducted at the Pacific Proving Grounds between 1946 and 1958. The survey consisted, in part, of an aerial radiological reconnaissance to map the external gamma-ray exposure rates over the islands of each atoll. The logistic support for the entire survey was designed operation. As a secondary appropriate terrestrial phase and marine of the survey, samples from pertinent food chains to those to to accommodate shore assess parties the this collected radiological individuals residing on the atolls, may in the future reside on some of the presently uninhabited atolls, dose who or who collect food from these atolls. Over 5000 terrestrial and marine samples were collected for radionuclide analysis from 76 different islands. Soils, vegetation, indigenous animals, and cistern water and groundwater were collected from the islands. Reef and pelagic from fish, clams, lagoon water, and sediments were obtained the lagoons. A considerable generated from the amount analyses of radionuclide of these samples. of the program will appear in separate reports. series we describe the general operation of the concentration Results In the survey, data has from different first report been phases of this the type and quantity