Impact assessment of naturally occurring radioactive materials on the public from gold mining and processing at Newmont Golden Ridge Limited, Akyem, Eastern Region of Ghana

Baseline radioactivity levels of naturally occurring radioactive materials within the operational area and surrounding communities of Akyem Gold Mine of Newmont Golden Ridge Limited of Ghana were determined based on direct gamma-ray spectrometry to quantify the radionuclides of interest, namely, 238 U, 232 Th, and 40 K in soil samples. The average activity concentrations of 238 U, 232 Th, and 40 K in the soil samples were 11.90, 11.39, and 139.71 Bq/kg, respectively. For the water samples, the concentration values of gross-alpha and gross-beta for all the water samples were below the Ghana Standards Board (now Ghana Standards Authority) and World Health Organization recommended guideline values for drinking water quality. The annual average effective dose to the public due to gamma ray exposures from the soil samples was estimated to be 0.03 mSv which is below the UNSCEAR 2000 average reference level of 0.07 mSv for public exposure control. The results obtained in this study also show that radiation levels are within the natural background radiation levels found in literature and compare well with the results of similar studies in Ghana.