Abstract
In view of the geological arrangement and the long historic activities of gold mining
in the Gauteng Province in South Africa, uranium bearing minerals have been
exposed at or near the surface. The mine dumps around the gold mines in the
Gauteng Province were assumed to be potentially hazardous and contain elevated
levels of naturally occurring radioactive materials (NORM). There is a potential
increase of radon in the area, since the soil in the mine dumps contains radium-
226 (the parent radioisotope of radon-222) and it could pollute the nearby rivers
and streams. Rivers running towards West and South of the Gauteng province
originates mainly from the mining areas whilst those running towards the East
and North of the Province are not necessarily originating from the mining areas.
The current study was carried out to determine the level of radon and the possible
over exposure of the public to radon concentrations from twenty-five rivers and
tributaries in Gauteng Province. Fifty water samples were collected from different
regions of the province including those areas around the mine dumps and those
that are far but in the residential areas. The samples were analyzed for radon
concentration. Three different brands of commercially available water were also
studied. Due to its reliability for laboratory and field determination of radon concentrations
in the current study, the alpha-spectrometry (α spectrometry) technique
was applied using RAD-7 instrument.
Standard water samples were used to calibrate the detector of choice in this study,
and the Liquid Scintillation Counter (LSC) was used as a reference detector. The
α spectrometry method was optimized to count the α particles emitted by 218Po
and 214Po in secular equilibrium with their parent, 222Rn. The variation of radon...
M.Phil. (Nuclear Energy Studies)