Protecting people from the impact of uranium mining
Mining has the potential to impact on people by a number of means, both physically and socially. The focus of the Supervising Scientist program is assessment of the biophysical impact of mining on people.
Radiological (ie radiation) exposure is a particular issue with uranium mining, in contrast to other types of mining. Such exposure may occur in the following ways:
- inhalation of the progeny of the radioactive gas radon;
- inhalation of radioactive dust particles;
- direct irradiation from outside the body, primarily by gamma rays or in some cases beta radiation;
- ingestion of radionuclides (eg uranium or radium) in food or water.
For workers at an open cut mine such as the Ranger uranium mine, radiological exposure due to radon progeny is generally less important than exposure from dust or gamma radiation. However, exposure to radon progeny can be very important in the case of underground mine workers. At Ranger uranium mine workers are monitored routinely for radiological exposure from direct irradiation and inhalation.
For members of the public, the most important pathways for an operating mine are generally radon transport and ingestion of radionuclides following surface water transport. For a rehabilitated mine over the short term, the most important pathways are likely to be inhalation of radon progeny and radioactive dust resuspension, and direct irradiation. Over the long term, groundwater and surface water transport of radionuclides and/or bioaccumulation into edible animals and plants that feed or grow on site or associated waterbodies may become more significant.
A useful, short description about radioactivity, the types of radiation found in nature, the process of radiation exposure and how it is measured, the risks associated with exposure and the dose received can be found at www.arpansa.gov.au/RadiationProtection/basics/index.cfm
Radon and automated weather stations (Photo: B. Ryan)
Bush beans collected in Kakadu as part of the eriss bushtucker project (Photo: B. Ryan)
Some relevant publications
Medley P, Ryan B, Martin P and Bollhöfer A, 2007. Rapid determination of radionuclide activity concentrations in contaminated drinking water. Radiation Protection in Australasia 24, 2, 2-8.
Sauerland C, Martin P & Humphrey C, 2005. Radium 226 in Magela creek, northern Australia: Application of protection limits from radiation for humans and biota. Radioprotection, Suppl. 1, vol 40, S451-S456.
van Dam R, Humphrey C & Martin P, 2002. Mining in the Alligator Rivers Region, northern Australia: Assessing potential and actual effects on ecosystem and human health. Toxicology 181–182, 505–515.