The transport and deposition of radionuclides discharged into creek waters from the Ranger Uranium Mine

The Ranger uranium mine in the Alligator Rivers Region of Australia's Northern Territory has been operational since 1981. Critical pathway analysis has shown that water transport of radionuclides from the mine site could be an important route for radiation exposure of members of the public; in the short-term such exposure could be as a result of the direct discharge of effluent waters into the nearby Magela Creek and in the long-term as a result of seepage of water from tailings repositories or the transport of erosion products from the rehabilitated site. In order to estimate the radiation exposure of the public from such processes it is necessary to model the transport of radionuclides in the creek and its associated floor plain. Such a model has been developed for radionuclides in the particulate phase by studying the transport and deposition of naturally occurring radionuclides. The two major components of this program consisted of measurements of concentrations of all the long-lived nuclides of the uranium series in the waters of Magela Creek and in the sediments of the flood plain