Analysis of Natural Radioactivity and Radiation Exposure Levels in Eburru Geothermal Field, Kenya

Authors(3) :-Solomon Wangila Namaswa, Collins Okoth, Brian Makori

In Kenya, the use of geothermal energy for power supply has becomes increasingly attractive as part of an alternative energy mix and from the current rate of geothermal installation it may soon overtake hydro as the leading source of energy. Although geothermal energy has been termed as clean, risks associated with the use of deep thermal fluids require intensive evaluation and communication made to the community and with the public since natural radioactivity is crucial for the earth system as the slow decay of radioactive elements produces approximately half of the heat that drives major earth’s processes such as continental drift, ocean spreading and plate tectonics. The results of a survey on the radionuclide concentration undertaken in Eburru geothermal field in different rock formations are hereby presented. This research measured activity concentrations of the naturally occurring radioactive elements 40K, 238U, and 232Th by use of NaI(Tl) gamma-ray spectrometer, estimated the absorbed dose rate, annual effective dose rates and the hazards index due to natural radionuclides and their decay products in Eburru geothermal field. The mean activity concentrations concentration of 238U, 232Th and 40K were 70.521±10.48Bqkg-1, 50.65±5.13Bqkg-1 and 588.511±156.14Bqkg-1 in rock samples. The average absorbed dose rates, annual effective dose rate and hazard index in rocks samples were found to be 87.71± 6.44 nGyh-, 0.11±0.01mSvy-1 and 0.50±0.03. From the obtained results, the studied hazard indices were within the world acceptable safety limits and therefore human exposure to radiation is within safety levels. This indicates that the level of the studied radioactive elements in geothermal rocks within Eburru geothermal field is within the acceptable range.

Authors and Affiliations

Solomon Wangila Namaswa
Department of Physics, Multimedia University of Kenya
Collins Okoth
Department of Electrical and Electronic Engineering, Multimedia University of Kenya
Brian Makori
Department of Physics, Multimedia University of Kenya

Geothermal Field, Radioactivity, Dose Rate, External Hazard Index

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Publication Details

Published in : Volume 4 | Issue 1 | January-February 2018
Date of Publication : 2018-02-28
License:  This work is licensed under a Creative Commons Attribution 4.0 International License.
Page(s) : 841-846
Manuscript Number : IJSRSET1841131
Publisher : Technoscience Academy

Print ISSN : 2395-1990, Online ISSN : 2394-4099

Cite This Article :

Solomon Wangila Namaswa, Collins Okoth, Brian Makori, " Analysis of Natural Radioactivity and Radiation Exposure Levels in Eburru Geothermal Field, Kenya, International Journal of Scientific Research in Science, Engineering and Technology(IJSRSET), Print ISSN : 2395-1990, Online ISSN : 2394-4099, Volume 4, Issue 1, pp.841-846, January-February-2018.
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