Assessment of natural radioactivity in soil and rock samples round el-obeid refinery, Sudan

This Study is primarily conducted around El-Obeid refinery, North Kordofan State to contribute overall strategic national programme of radiation monitoring to create a radiation map for country, to be useful as a reference in the any case of environmental impacts. The measurements soil and rock samples were performed measured by gamma spectrometry with Nal(Tl) detector. The average activity concentrations of ''226Ra, ''232Th and ''40K determined were 30.11±4.49, 28.19±5.82 and 301.28±62.95 Bq/kg, respectively in soil samples.On the other hand the activity concentration of radionuclides ''226Ra, ''232Th and ''40K on rock samples were 23.80±6.40, 25.82±5.37 and 315.37±94.40 Bq/Kg, respectively. The absorbed dose rates and annual effective dose were estimated.However, the absorbed dose rates was found to be 32.03±4.04 nGy/h and 29.42±6.52 nGy/h for soil and rock samples, respectively and the corresponding annual effective dose to the population due to exposure to natural radionuclides (''226Ra, ''232Th and''40K) for soil and rock samples were 39.31±4.96 and 36.11±8.00 μSv/y, respectively. However, the results showed that the radioactivity level in area under consideration were less than the global data reported in the UNSCEAR publications for normal background areas.