Metal mining processes in general, cause environmental heavy metal pollution over time. Extraction and processing of metals, therefore, comes with the responsibility of ensuring that any of by-products are treated before disposal as requirement. This study determined the levels of heavy metal concentrations; cadmium, arsenic, chromium, mercury, lead, copper and zinc in environmental samples, in order to assess the extent of heavy metal pollution in Kilimapesa Gold mine processing plant in Narok County. A total of forty-one (41) samples, from nineteen (19) sites, namely; nine (9) sub-surface soils, eight (8) sediments, fourteen (14) Sodom apple (Solanum incanum) leaves and ten (10) water samples, from the nearby river streams were analysed for heavy metal content. The sediments, soils and plants samples were dried, crushed, sieved and made into thin pellets for analysis using the EDXRF spectrometer available at the Department of Physics, University of Nairobi. Gallium was added to the water samples as an internal standard, mixed before analysis for heavy metal content, using the TXRF spectrometer at the Ministry of Petroleum and Mining Laboratories. The metals concentrations levels in water samples (mg/l) were distributed as follows; Cd (< 4.4), Hg (< 1.0), As (< 1.5), Cr (< 6.5 - 391), Zn (< 3.0 -187), Ni (< 4.0 - 830), Pb (< 3.0) and Cu (< 1.1 470). The highest concentrations were recorded at the confluence of the river streams; this could be due to an accumulation of sediments at the convergence point. The levels in soil samples (mg/kg) were; Cd (< 3.00), Hg (< 1.9-23.5), As (14.6 – 935), Cr (111 - 406), Zn (61.5-156), Ni (24.4-164), Pb (26.6-148) and Cu (42.3-174. The variations of the metals concentration levels in Sodom apple (Solanum incanum) samples (mg/kg) were; Cd (< 3.0), Hg (< 1.9-3.2), As (< 1.1 - 2.0), Cr (< 3.0-10.0), Zn (24.5-40.9), Ni (< 2.0 - 14.3), Pb (< 2.07.2) and Cu (17.9-33.3). These levels are comparable to those found in other undisturbed environment, except for arsenic and lead, which may be attributed to mining activities in Lolgorian.There was a significant difference in metals levels among the three media sampled following ANOVA analyses. Pearson's correlation for all trace elements of interest in Sodom apple (Solanum incanum) and soils were very weak except for mercury. The same trend is replicated betweensoilsand water, and between water and plants, for all heavy metals of interest in this study, except for Zn and Ni, respectively. In general, Kilimapesa soils are moderately to extremely contaminated with these metals. The study therefore recommends the introduction of heavy metals bio-accumulators, like water hyacinth in the waste disposal treatment ponds and for enforcement of disposal regulations and for epidemiological studies.

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