Analysis of Naturally Occuring Radioactive Materials (NORM) in surface water in mining areas of Kasese district.

Abstract

Mining is the process which involves extraction of minerals and geological materials from the earth. This activity may have a detrimental effect on the environment hence impact health of animals and human. The concentrations of the naturally occurring radioactive materials (NORM) in mineral concentrates, water, soil, products increases during processing of minerals. The main aim of this study was to analyse the concentration levels of radioactivity levels of surface water in mining areas of Kasese district found Western Uganda. A total number of seventeen (17) samples were collected from surroundings of Hima, Lake Katwe, Kilembe mines and Kasese Cobalt Company Limited sampling points. The radioactivity levels were determined using the Gamma ray spectrometry, using High Pure Germanium detector. The concentrations of levels of activity of the radionuclides Ra-226, K-40 and Th-232 in the water samples were identified and measured. Gamma index, Radium equivalent, external hazard and internal hazard radiological risk parameters were therefore used to assess the radiation hazards for the radionuclide measurements analyzed in the water samples. The major nuclide in abundance was determined to be K-40 in all areas. The average activities of K-40, Th-232 and Ra-226 were found to be 4374.6 Bq/L, 170.5 Bq/L, and 290.5 Bq/L respectively. These concentrations exceeded the world UNSCEAR activities with the minimum activities of K-40, Th-232 and Ra-226 obtained at 2955.2 Bq/L from Hima A8, from Hima A8, 0 Bq/L from Hima A3, KCCL A1 and A4, 188.6 Bq/L from Hima A3 respectively. The maximum activities of K-40, Th-232, and Ra-226 were obtained at 5995.9 Bq/L from KCCL A16, 383.3Bq/L from Hima A13, 409.0 Bq/L from KCCL A16 respectively. The levels of radiation were used to measure the radiation hazard that the people living around the mining areas were exposed to which were found to be higher than ICRP limits. The results from this study will be used as reference to monitor the environmental impact of the mining activities and geology studies. According to the results of this study, mining activities and presence of various minerals in this area lead to an elevation of the radioactivity levels and radiological risk to residents in Kasese district.