Stream Sediment as Pollution Indicator within Shikira Gold Mining Site, Niger State, North-central Nigeria

Abstract

The quality of stream sediment within Shikira gold mining sites was investigated in this study as they provide good information on the impact of anthropogenic activities in the area. Lithological mapping of the area revealed schist and granites while the structural analyses indicate NE-SW fracture trend. The results of the laboratory analyses showed that the mean concentration of mercury, cadmium, lead and arsenic were above the respective crustal abundance of the elements thereby signifying pollution. Further application of pollution indices such as geo-accumulation index, contamination factor, degree of contamination, elemental contamination index and metal pollution index on the data further confirmed that the sediment in Shikira gold mining sites are seriously polluted with mercury, cadmium and lead, moderately polluted with arsenic, lightly polluted with iron and copper and very lightly polluted with manganese, zinc, nickel and cobalt in the order of: Hg > Cd >Pb> As > Fe > Cu > Mn > Zn > Ni > Co. The study recommends that washing of gold along the river channel should discontinue and the miners should be trained on modern mining techniques which are environmental friendly. Water from the stream within the mining area should not be used for domestic or drinking purposes including livestock in the present condition except after remediation, due to health implications of the identified metals. Regular monitoring of the sediment quality in the area is advocated.