The Impact of Wastewater from Artisanal Mining on the Pollution of Contaminated Sites: A Case Study of Betare-Oya in East Cameroon

The aim of this work was to evaluate the impact of the wastewater from artisanal mining on the pollution contaminated sites in the Betare-Oya locality in East Cameroon. Water samples were collected from the Mbal stream exposed to artisanal mining on the upstream and downstream, and analysed for contamination loads in the laboratory. Water samples were taken on four different positions of the stream course and analysed in the laboratory. The laboratory analysis quantified the loads of pollutants including the heavy metals in the water samples and their physicochemical and bacteriological parameters. Results show that the levels of the water stream contamination exceeds the upper limits of the contaminations that WHO (World Health Organisation) standards allows. The suspended solid content, colour, turbidity and total coliforms were 573 mg/l, 3683 Pt-Co/l (Platinum Cobalt Colour per 1 l of sample), 468 NTU (Nephelometric Turbidity Unit) and 171×103 CFU/100 ml (Colony Forming Unit per 100 ml of sample) respectively. The analysis of heavy metals contamination showed its levels are lower than the detection limits of the plasma emission spectrometry technique. The good correlations of the major chemical elements in the water samples revealed by the study, indicates that they originate from the alteration of rocks.