**1. Introduction**

Water from surficial and underground sources is critical for the sustenance of all life forms on earth. Surface water is arguably the most easily available and well-harnessed drinking water source since creation. In tropical rainforest regions, surface water resources are the utilized and source of water supply to meet the demands of domestic, industrial and agricultural purposes. However, certain human activities and natural processes may alter the surface water quality, thereby limiting its ease and scope of reliability and usage. Such natural processes may include

earthquakes, volcanic eruptions, landslides and hurricanes, and when such events are occurring at local and regional scales, they may alter the quality of surface water sources. Anthropogenically, the progressive industrialization and application of scientific methods in improving various livelihood demands by humans may result in the generation of varied amounts of wastes of varying toxicities, which when not properly handled may serve as potential sources of pollution to the environment including surface and groundwater resources.

One key activity of man that contributes to the pollution of drinking water sources is illegal artisanal gold mining activities. Globally, approximately 100 million people are considered to be directly or indirectly involved in such operations for their livelihood [1]. In Ghana, however, artisanal gold mining is estimated to have begun several decades ago with approximately one million people directly or indirectly involved [2]. The areas of operations are generally, rural settings with few peri-urban centers and a much fewer large urban centers that depend on both surface and groundwater resources for domestic, agricultural and industrial purposes. The rapid growth in urban and peri-urban population, coupled with the ever-increasing unemployment have resulted in the greater proportion of local and migrant youth (male and female) in Ghana, Burkina Faso, Mali Niger as well as Chinese nationals, getting in involved in illegal artisanal gold mining.

Despite the positivity of artisanal gold mining to the socio-economic development of societies, especially in most developing countries like Ghana [3], illegal artisanal gold mining activities utilizes crude and rudimentary techniques and environmentally unfriendly extractive processes. Examples may include but are not limited to the extraction of shallow alluvial gold deposits; diversion of streams and river courses to expose otherwise inundated beds for excavation; washing of alluvial ores at close proximities and many cases, inside river and stream channels. These may contribute to land degradation and water quality deterioration among others [4]. Furthermore, the utilization of mercury and cyanide to leach and/or amalgamate the gold during extraction, have been found to contribute to the release of harmful metals to the environment [5, 6]. These metals when found above permissible limits in drinking water and/or the food chain could be detrimental to human health and sustenance of the ecosystem [7].

According to [8], there is a great national concern with regards to the increasing activities of environmentally unfriendly mining activities in Ghana. The Ahafo-Ano South District in the Ashanti Region of Ghana is a predominantly rural area with few peri-urban and urban dwellings, where illegal artisanal gold mining activities occur. This has led to an influx of various people majority of which are youth from different parts of Ghana. Groundwater per the national water policy of Ghana [9] is the major source of potable water in rural Ghana. The observed rapid influx of people into the area to partake in the illegal artisanal gold mining requires that large quantities of groundwater must be exploited to meet the ever-increasing potable water demand. To this end, an evaluation of the quality groundwater in the area becomes essential. Poor drinking water quality, according to [7] can expose humans to potential health risks. Groundwater generally is considered to be of better quality, compared to surface water in terms of potability. Deterioration in quality, however, may occur over time due to certain natural processes and anthropogenic activities. According to [10], some of the natural processes may include hydrogeochemical processes such as water-rock-interaction, soil-water interaction, cationic exchange reactions, mixing of waters; certain biological processes including selective uptake by vegetation and evapotranspiration. Anthropogenic activities that may result in leachates into groundwater resources may come from agricultural fields that utilize especially, agro-chemicals and manures, municipal and urban wastewater sites, mining activities and mine waste disposal sites, domestic and industrial effluents, etc.

*Effects of Illegal Artisanal Gold Mining Operations on Groundwater Quality in Ghana… DOI: http://dx.doi.org/10.5772/intechopen.100242*

Consequently, this study is aimed at assessing the quality of groundwater resources for drinking purposes and to evaluate the potential risk(s) to human health in the Ahafo-Ano South District of Ghana, which is an artisanal gold mining area. In the authors' view, this will also provide a framework for any future groundwater quality monitoring and evaluation exercise to ensure sustainable utilization of the resources.
