Spatial Analysis of Artisanal and Small-Scale Mining in the Tarkwa-Nsuaem Municipality of Ghana

Abstract

Abstract

In recent times there have been lots of public outcry on the environmental and public health and safety effects of Artisanal and Small-scale gold Mining (ASM) and the need to monitor ASM activities for reclamation purposes. To effectively develop and deploy policy responses to the environmental and human health effects of ASM, knowledge of the locations and distribution of ASM sites is a prerequisite. However, information regarding ASM hotspots and spatial distribution, the scope and types of ASM operations are hard to find. Therefore, this research was designed to use satellite-based data to map out ASM sites, focusing on the Tarkwa-Nsuaem municipality as the study area. Several image processing techniques were applied on a Landsat 8 satellite image downloaded from the US Geological Survey website. The image processing resulted in the identification of 221 clusters of ASM sites, representing 12.72% of the total size of the study area. To further explore the effects of these ASM sites, Areas of Interest (AOI) including forest reserve, rivers, large-scale mines and urban settlements were defined. By selecting and analysing the location and distribution of the ASM sites in relations to the AOI, the study was effective in identifying environmentally sensitive and critical areas warranting the urgent attention of society to mitigate the health, safety and ecosystem service effects of ASM in the study area. By identifying the environmental sensitive areas being affected by ASM, the findings could support the prioritisation of reclamation efforts.

Keywords: Artisanal Small-Scale Mining, Satellite Image, Environmental Effect, Public Health and Safety