Assessment of the Potential Radiological Impact of Residual Contamination in the Maralinga and Emu Areas

The report presents the results of an assessment of potential doses to future inhabitants of the Maralinga and Emu areas of Southern Australia, where nuclear weapons tests in the 1950s and 1960s have resulted in widespread residual radioactive contamination.Annual effective doses of several millisieverts would be expected to result from continual occupancy within contours enclosing areas of several hundred square kilometres. Larger predicted annual effective doses — of the order of 0.5 Sv — would be expected to occur from 100% occupancy in the small regions immediately surrounding the test sites, but continual occupancy of such areas is highly unlikely because of their small size. The most significant dose pathways are the inhalation of resuspended activity and ingestion of soil by infants. An analysis of the effects of uncertainties in the dose calculation has indicated the uncertainty distribution on predicted doses from the inhalation pathway.