Long-term ecological behaviour of abandoned uranium mill tailings : 4. Biomass transfer of RA-226, PB-210 and uranium in terrestrial and semiaquatic areas and related food chains

Abstract

Environmental pathways of long-lived radionuclides from uranium mill tailings to the environment should be evaluated in communities which as closely as possible reflect those of the future. Typical early colonizer species have established on uranium mill tailings two decades after abandonment. The growth characteristics of these early colonizers have been evaluated as well as the radionuclide transfer to the plants in terrestrial and semiaquatic areas on uranium mill talilings in the Bancroft, Elliot lake and Uranium City areas. This information is placed into an ecological context for the present and the future communities. The specific objectives of this work are to arrive at estimates of mass transfer of radionuclides from the tailings to indigenous pionnering communities which have developed on inactive or abandoned uranium mill tailings sites in the past two decades. These estimates are related to consumption by fauna, which may graze on these specific plants. A review of the ecological dynamics of the vegetation community and biogeochemical cycles on the waste sites is attempted to forecast long term trends.