*o5/- soll-water cycling and the associated cycling and availability of radionuclides to plants Is essentia! for accurate dose assessments and estimates of the potential long-term use of the atolls. Additionally, we will conclude the analysis of the coconut of] and dried pulp and develop a final dose assessment during FY 1979. Enewetak Atoll! We will maintain the test gardens of the long-term subsistence crops (pandanus, coconut, and breadfrult). These plants are being fertilized as part of our experiment and they appear to be growling much more rapidly than the unfertilized plants. Therefore, we may be able to harvest the edible products from these crops during FY 1979 and determine uptake and concentration factors for the fruits. In addition, we will continue to sample and analyze the coconut and pandanus trees on Belle, Clara, Irene, Janet, Sally, and Tilda Islands to determine the residence times of 137¢5, 9bsp) and plutonium in the atoll! ecosystem. We also will field either the Initial or the follow-up resuspension study on Engebi Island. Continued sampling of soil moisture, water cycling, radionuclide concentrations in soil, humus, litter, and canopy as well as the measurement of micrometeorolocical parameters at Engebi tstand will provide the necessary input to thoroughly evaluate the controlling mechanisms of radionuclide transport and cycling in the atolls. 18. EXPECTED RESULTS IN FY 1980: We should have sufficient data, even from the long-term crops, to develop a genera! model for predicting doses from other islands and atolls that do not now support subsistence crops but which may in the specific options for remedial action can be proposed and evaluated. 19. MAJOR MATERIALS, EQUIPMENT, AND SUBCONTRACT ITEMS: vO ZO We also will complete a general evaluation of the resuspension pathway and of the potential dose due to the transuranic radionuclides. By FY 31980, there should be sufficient data available to develop a model of radionuclide cycting In the atoll ecosystem so that more IN wa future. FY 1980 Aerosol particle analyzer (2) Data logger/microprocessor (2) Wescor soil psychrometer (2) Tape transcriber $26 ,000 6,000 2,400 600 $ 6,000 2,400 600 tf FY 1979 tA Equipment 8 O8e Estimated Cost