Groundwater pollution on the Zambian Copperbelt: deciphering the source and the risk.

School of Geography and the Environment, Oxford University, Oxford OX1 3TB, UK.
Science of The Total Environment (Impact Factor: 3.16). 08/2004; 327(1-3):17-30. DOI: 10.1016/j.scitotenv.2003.08.028
Source: PubMed

ABSTRACT The protection of groundwater resources is of great importance in many semi-arid and sub-tropical environments. The Copperbelt of Zambia is one such environment and due to the high proportion of tailings impoundments, residue heaps, high-density informal settlements and extensive sulfidic ore deposits in the region, its groundwater resources are under threat of anthropogenic or geogenic pollution. One such pollutant plume is investigated in this study, to determine its origin, rate of progression and the environmental and health risk it poses. Geological and geochemical investigation strongly suggests an upslope tailings impoundment as the source of contaminants, with the edge of the pollution plume lying 500-700 m downstream of the impoundment. Although cobalt, nickel and zinc concentrations were elevated within the polluted groundwater, the concentrations are low as a result of sulfide precipitation and adsorption within the aquifer, and meets guidelines for drinking water quality. Attenuation of heavy metals is linked to tailings dam and aquifer pH, with the high buffering capacity of each implying that these processes of attenuation are likely to continue removing harmful metals from the aquifer. Thus, it appears unlikely that the contaminated groundwater will present a major environmental risk at this site. However, tailings impoundments are widespread throughout the Copperbelt: sites with low tailings dam buffer capacity and in catchments on crystalline bedrock geology, groundwater pollution through tailings dam leachate may liberate high concentrations of heavy metals into the shallow groundwater, potentially posing a serious human health risk to the communities using the water resources and an environmental risk to the downstream ecosystems.

  • [Show abstract] [Hide abstract]
    ABSTRACT: Chemical and microbiological analyses of deep and surface water were conducted in Niakhar, a densely populated zone 200 km2 in area in the Senegalese Sahel, 150 km east of Dakar, the capital.We identified approximately 500 water points there randomly selected 71 for chemical analyses and 40 for bacteriological analyses. A very strong mineralization of deep as well as surface water was observed. In one third of the water points sampled, fluorine concentrations, and in two thirds, sodium chloride concentrations exceeded World Health Organization and European Union guidelines. Sodium, potassium, calcium and manganese concentrations also exceeded recommended levels in most water sources. These levels appeared to correspond to several specific water distribution networks. Contamination by E. coli was low, but contamination by faecal streptococcus was very high in most water points, including the terminal hydrants, could be due to distribution and storage conditions that favor bacterial multiplication more than to intense pollution of faecal origin.
    Environnement, Risques & Santé 10/2007; 6(5):373. · 0.18 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The gold mining plant of Oman was studied to assess the contribution of gold mining on the degree of heavy metals into different environmental media. Samples were collected from the gold mining plant area in tailings, stream waters, soils and crop plants. The collected samples were analyzed for 13 heavy metals including vanadium (V), chromium (Cr), manganese (Mn), nickel (Ni), copper (Cu), cadmium (Cd), cobalt (Co), lead (Pb), zinc (Zn), aluminium (Al), strontium (Sr), iron (Fe) and barium (Ba). The water in the acid evaporation pond showed a high concentration of Fe as well as residual quantities of Zn, V, and Al, whereas water from the citizens well showed concentrations of Al above those of Omani and WHO standards. The desert plant species growing closed to the gold pit indicated high concentrations of heavy metals (Mn, Al, Ni, Fe, Cr, and V), while the similar plant species used as a control indicated lesser concentrations of all heavy metals. The surface water (blue) indicated very high concentrations of copper and significant concentrations of Mn, Ni, Al, Fe, Zn, lead, Co and Cd. The results revealed that some of the toxic metals absorbed by plants indicated significant metal immobilization.
    Central European Journal of Engineering. 2(2).
  • [Show abstract] [Hide abstract]
    ABSTRACT: This paper examines the contribution of forest provisioning ecosystem services (FPES) to rural households and assesses the contributions of forests to the annual incomes of households in Africa’s Miombo woodlands. The study employed focus group meetings, in-depth interviews, and interviews of households, as stratified by wealth class and head of household gender in Copperbelt, Zambia. The results show that FPES are vitally important in providing food, medicine, fodder, and construction materials to rural livelihoods. FPES provided 43.9 % of the average household’s income and contributed a 10 % income equalisation effect among households, as revealed by the Gini-coefficient analysis. Poorer households received a lower mean annual income from forests than did their intermediate and wealthy counterparts, but in relative terms, forest income made the greatest contribution to the total household incomes of poor households. When stratified by gender, forests contributed 44.4 and 41.8 % of the income of male- and female-headed households, respectively. The study indicates that wealth, rather than gender, was the key determinant of a household’s engagement in the sale of FPES. The inter- and intra-community differentiation in the use and sale of FPES, as revealed in this study, enables more effective targeting of forest management interventions and informs efforts to reconcile the goals of poverty reduction and forest conservation.
    Population and Environment 12/2013; · 1.46 Impact Factor

Full-text (2 Sources)

Available from
Jun 6, 2014