OFFICIAL USE ONLY (shown in Figure 4). The radionuclides are concentrated in the surface 2 inches of soil in undisturbed areas. Soil samples analyzed for plutonium (Table 1) were generally selected from areas with the highest levels of gamma radiation. Exceptions were those obtained from the camp area at Bikini Island and along the runway at Eneu Island, Soils were collected in 1967, 1969, and 1970 from individual soil pits. The area of higher radiation at Eneu Island was one of the few locations relatively undisturbed at Eneu and had an area of approximately 50 square feet; the sample from this area consisted of a composite of four collections. Seven soil samples were analyzed by both SWRHL and University of Washington for an inter-laboratory check (Table 2). 3.3 TRITIUM IN GROUND WATER Tritium in well water is present at low concentrations; the maximum value found was 14 pCi/ml, or 4300 tritium units (at Nam Island) whereas at Bikini and Eneu Islands, the concentration was 2 pCi/ml, or approximately 600 tritium units. (See Figure 3 for well point locations on Bikini.) These values fall within the range of tritium concentrations in surface waters of the United States in 1966, It has been shown that there is approximately 10,000 times more tritium in "bound" water than in "free" water in soils at Eniwetok Atoll, however, there is little exchange of the bound water with the free water. (Free water is that released or extracted by freeze drying. Bound water represents additional water which could be released upon combustion of the sample.) Hence it is probable that there will be no major changes in the tritium concentration of well water at Bikini Atoll. 4. RADIONUCLIDES IN FOOD The values of radionuclides observed in food items other than land plants are presented in Table 3. 4.1 EDIBLE PLANTS Coconut, arrowroot, and pandanus samples were collected in 1967 and 1969 and analyzed (Table 4). Coconut samples were collected from 13 different locations on Bikini in 1969. Green coconuts were used for almost all samples and the meat and milk were analyzed separately. Only 137¢cs and 90Sr were detectable in any of the samples. Tritium analyses were performed on the milk from selected coconuts but all results were below the lower limit of detection (0.4 pCi/ml). 4.2 FISH The fish collected and analyzed are in two main categories: reef fish and pelagic fish. The reef fish, an important item in the Marshallese diet, are caught by throw net while the pelagic fish are caught by trolling. 11 OFFICIAL USE ONLY