4.2.4 Treatment with Potassium Fertilizer. Exploratory experiments have shown that potassium fertilizer at high levels will the specific-activity of cesium-137 in plants reduction the presumably is uptake effective of against the (27N, 28, Appendix B). the result of competitive cesium-137., The cesium extent levels to on reduce blocking by potassium of which Bikini Such such blockade Island is not would be known; to estimate this, support has been requested for pilot trials that would begin in the fall of 1984. | Although such treatment may not be powerful the high levels of cesium-137 on Bikini enough for Island, it maybe of use in marginal or moderate cases of contamination, for example, Enedrik, where 50 percent reduction in plant uptake would lead to a diet that meets the standard. Potassium treatment might also be used to truncate the end of the 80-year waiting period for Bikini if that island is allowed to go untreated. The advantage of potassium treatment is that the topsoil is retained, and in fact, its productivity would be improved by the fertilizer treatment. treatment after cost. year activity On until to an The increased yields would partly compensate for the the other spontaneous acceptable hand, the treatment decay of the level. must be cesium-13/ Furthermore, the continued reduces treatment decontaminate the ground water. year specificdoes not . The cost of such a treatment would be of the order of $500 per hectare (.01 km?) , The cost of radioactivity monitoring also must be allowed for. and total costs, however, cannot be stated now with any The annual precision because it is not yet known how frequently the individual treatments must be given. 4.3 Soil Removal Removal is the direct way to deal with contaminated soil. clearing of vegetation, the contaminated soil 2000030. se After is excavated and disposed of