Impact of Artisanal and Small-Scale Mining on Water bodies and Treatment: The Case of Birim River Basin in Ghana
Abstract
Water bodies, the source of drinking water for many rural households in mining areas are at risk of contamination due to artisanal and small-scale mining (ASM) activities. Water quality, therefore, remains a topical issue for policymakers and researchers.
This research sought to achieve three objectives: firstly, to evaluate the effectiveness of existing policies and regulations about ASM in protecting waterbodies. Secondly, to determine the impact of ASM on waterbodies, health and livelihood of inhabitants in mining communities and thirdly, to remove heavy metals from water using locally available bio-adsorbents such as moringa seeds, coconut and corn husks.
A survey of 400 respondents and 30 interviews were conducted in three mining communities that depend on water from the River Birim Basin, in Ghana, to assess the impact of ASM activities on water bodies, health and livelihood of inhabitants of the affected communities. One hundred water samples were collected from the Birim River, tributaries, groundwater and mine ponds in the wet (June-September) and dry seasons (December to March), to determine the water quality and the concentrations of heavy metals such as Arsenic, Lead, Iron, Mercury, Cadmium and Manganese. Water containing heavy metals were treated using bio-adsorbents in the laboratory. An evaluation of existing policies related to ASM in Ghana was also carried out.
The findings indicated that a lack of awareness and ineffective implementation and enforcement of the policies, in addition to limited knowledge of the impact of ASM activities on water bodies contributed to the pollution of water bodies. Heavy metal concentrations exceeded the WHO limit for drinking water in most of the samples especially in the dry season. Water from the Birim Basin was found to be contaminated and not safe for drinking and other domestic purposes and therefore treatment of the water is necessary. The bio-adsorbents developed in the present research successfully removed some arsenic, iron and lead from the water. These bio-adsorbents can therefore be used by communities dependent on the Birim Basin to reduce heavy metal related health risks. Research findings are expected to provide relevant information for policymakers, environmental experts and other stakeholders in enhancing water quality.