Radioactivity in Surface Soils Around the Proposed Sites for Titanium Mining Project in Kenya

M. K Osoro, I. V. S. Rathore, M. J Mangala, A. O Mustapha

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DOI: 10.4236/jep.2011.24053                

Abstract

Radioactivity measurements were carried out around Maumba and Nguluku villages, two of the proposed sites for titanium mining in the coastal area of Kenya. Samples of surface soils were analyzed using a HPGe gamma spectrometer. The average activity concentrations for ²²⁶Ra, ²³²Th and ⁴⁰K are 20.9 ±7.6, 27.6 ± 9.1 and 69.5 ± 16.5 Bqkg^–1<, respectively. The absorbed dose rates in air, calculated on the basis of the measured activity concentrations, range from 9.8 to 50.0 nGyh^-1, with an average of 29.2 nGyh^-1. These values are below the global population-weighted mean, and they should be considered when planning appropriate monitoring and surveillance programmes during the mining operation, as well as the reclamation and restoration programmes after mining.

Keywords

Radioactivity Measurements, Titanium Mining, Absorbed Dose Rates, Natural Background Radiation

Conflicts of Interest

The authors declare no conflicts of interest.

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