Natural radioactivity measurement of gold mine tailings in Vatukoula, Fiji Islands

Gold mining is one of the primary industry in Fiji, and it could expose the naturally occurring radioactive materials (NORMs) that may produce health risk to the people working in mining. The present study focuses on the assessment of soil samples in the vicinity of gold mining to assess the concentration of these nuclides. The average activity concentrations of Uranium ( 238 U), Thorium ( 232 Th) and Potassium ( 40 K) in the soil samples from the gold mining area in Vatukoula, Fiji were computed using NaI(Tl) detector. The activity concentrations varied from 30.7 Bq kg −⁡1 and 175.73 Bq kg −⁡1 for 238 U and 40 K with the absence of 232 Th in the decommissioned site. 19.49 Bq kg −⁡1 , 123.06 Bq kg −⁡1 and 86.86 Bq kg −⁡1 was determined for 238 U, 232 Th and 40 K of the commissioned sites respectively which is less than the world averages according to the United Nations Scientific Committee on the Effects of Atomic Radiation report 1, except for 232 Th which is expected to be higher due to the mineral composition of monazite derivatives. Our preliminary results on the activity of these radioactive nuclides demonstrate that the mining activities at Vatukoula poses no significant radionuclide hazard to the miners and the general public.