8. Determination of Natural Radioactivity and Hazard in Soil and Rock Samples in a Mining Area in Ghana

Abstract

The activity concentrations of natural radionuclides Ra, Th and K in soil, rock, waste and tailing samples
were measured by gamma spectrometry using high-purity germanium detector. In addition, radiological hazard
226 232 assessments due to these natural radionuclides were carried out. The average activity concentrations of Ra, Th
40 and K determined were 13.61 + 5.39 Bq/kg, 24.22 Bq/kg and 162.08 + 63.69 Bq/kg, respectively. The
average annual effective dose was 0.17 + 0.09 mSv. The average radium equivalent activity concentration in the
sample was 61.00 Bq/kg. The calculated external and internal hazard indices were less than unity with average
222 values of 0.16 and 0.20, respectively. The result of the Rn emanation fraction varied in a range of 0.51–0.80. The
results obtained show that soil, rock and waste materials that may be used for construction of buildings may not
pose any significant radiological hazards to the inhabitants in the study area.