Evaluation of Radiation Hazard Indices in Mining Sites of Nasarawa State, Nigeria
U. Rilwan *
Department of Physics, Nigerian Army University, P.M.B 1500, Biu, Borno State, Nigeria.
I. Umar
Department of Physics, Nasarawa State University, P.M.B 1022, Keffi, Nasarawa State, Nigeria.
G. C. Onuchukwu
Vice Chancellor’s Office, Nigerian Army University, P.M.B 1500, Biu, Borno State, Nigeria.
H. A. Abdullahi
National Agency for Science and Engineering Infrastructure, IduIndustrial Area, P.M.B 391, Garki, Abuja, Nigeria.
M. Umar
Department of Physics, Nigerian Army University, P.M.B 1500, Biu, Borno State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
This work evaluates the radiation hazard indices from some selected mining sites in Nasarawa West, using Sodium Iodide Thallium Gamma Spectrometry. Raeq ranged from 100.39-197.40 Bq/Kg with a mean 161.44 Bq/Kg, which is lower than the average of 370 Bq/Kg. The GADR ranged from 44.85 nGy/hr-90.71 nGy/hr with the mean 73.68 nGy/hr. which is also below the average of 89 nGy/hr for soil. The AGED ranged from 315.77 mSv/yr-640.91 mSv/yr with the mean 519.19. Which is above the threshold value of 300 mSv/yr. ACI ranged from 0.73-1.45 with the mean value 1.18 which is above the standard of unity. The AEDE (outdoor) ranges from 0.055 mSv/yr-0.111 mSv/yr with the mean 0.090 mSv/yr which is above the 0.07 mSv/yr standard permissible limit. The AEDE (indoor) ranged from 0.220 mSv/yr-0.445 mSv/yr, with the mean value 0.361mSv/yr. This is below the 0.45 mSv/yr threshold. The ELCR ranged from 00.770-1.558 with the mean value 1.265 and from 0.193-0.389 with the mean value 0.317 for outdoor and indoor respectively, which exceed the 0.29 X 10-3 threshold limit. The External and Internal Hazard indices ranges from 0.271-0.533 and 0.289-0.675 as well as mean values 0.435 and 0.512 respectively, which are below the threshold. Therefore, there may be serious radiological effects to the populace.
Keywords: Radionuclide, radiation, hazard indices, Nasarawa State.