Remedial Actions Significant reductions in dose can be achieved at atolls contaminated with different levels of radioactivity in the Marshall Islands. Welist here. five measures to achieve such reductions at Rongelap Island with reference to the effectiveness of the measures and associated monetary and environmental impacts. 1. Removethe surface soil (0 to 30 cm)in the area where the village will be established and for 10 to 15 m around each ofthe sites where houses will be built to minimize the external gamma and beta and alpha exposure in the areas where people spend most of their time. The additional cost to remove 15 to 20 cm ofsoil from the relatively small area included around each house and the village area would be minimal, compared with the overall costs of resettlement, since scraping and clearing is required to begin construction and resettlement. There would essentially be no adverse environmental effects from such an action. 2. Place a 10-cm layer of crushed coral ferto ilizs er con p tingsof as isis sup nit pro gen,' phosphogus, and or blocking the uptake of 137Cs j 197Cs, Sr, 239+240Py, and 241 Amar are es iM in the soil although the 137Cs uptake int o f greatly reduced. 4. Design adequate water catchment k so that fresh water will always be avai even during extended dry periods, thusa use of the contaminated ground water. A the reduction in the estimated dose f om the 0.05% of the estimated dose) is very mhch less than for the external gamma and terrest#iz community design. Again, apar radiological considerations, this mea be found acceptable because of the around the village site and in a 5-to 10-m radius around each house to provide some additional reduction in any beta and gamma rays emanating from the soil subsequentto the soil removal and cm of soil over the whole island also radiation. external and internal. greatly reduce exposure to any residual beta This should be acceptable, as it is common practice in Marshallese villages to use crushed coral around homes for both appearance and dust suppression. The combination of the soil removal and application of crushed coral can significantly reduce the external exposure and provide small reductions in internal exposure. 3. Treat the entire agricultural area of the island, where coconut, breadfruit, and Pandanus fruit are growing, with potassium chloride (KCl) or complete fertilizer (nitrogen, phosphorus, and potassium) to reduce the uptake of 137Cs into food crops. A high-potassium effectively the potential effective dofe This option, of the This would obviously [require nutrients and water-retention capaci coral soil. fertilizer can also be used in any family-type gardening for the same reason. The potential reduction in estimated dose from the food chain can be 90% or more. This salutary plan, coupled: with the soil removal and addition of crushed coral in the housing and village areas, could reduce the total estimated 30-y, integral effective dose at Rongelap Island from 0.0059 Sv (0.59 rem) to about 0.0026 Sv (0.26 rem). Furthermore, growth rate and productivity of some food crops will be increased if a complete expertise, the availability of which does now seem assured. a formidable problem of both accepta cost. 51 not