UNIVERSITY OF CAPE TOWN FACULTY OF ENGINEERING & BUILT ENVIRONMENT DEPARTMENT OF CHEMICAL ENGINEERING ASSESSMENT OF WATER POLLUTION ARISING FROM COPPER MINING IN ZAMBIA: A CASE STUDY OF MUNKULUNGWE STREAM IN NDOLA, COPPERBELT PROVINCE BY University of Cape Town LEE MUDENDA A thesis submitted in partial fulfilment of the requirements of the award of Master of Philosophy Degree in Sustainable Mineral Resource Development MDNLEE001 I The copyright of this thesis vests in the author. No quotation from it or information derived from it is to be published without full acknowledgement of the source. The thesis is to be used for private study or non- commercial research purposes only. Published by the University of Cape Town (UCT) in terms of the non-exclusive license granted to UCT by the author. University of Cape Town ABSTRACT Water pollution is recognized as one of the major environmental problems in the mining industry. This has been compounded with an increase in agriculture activities. Water pollution is a major problem on copper and coal mines throughout the world and Zambia, the focus of this study, is no exception. Worldwide freshwater resources, which provide important ecosystem services to humans, are under threat from rapid population growth, urbanization, industrialization and abandonment of wastelands. There is an urgent need to monitor and assess these resources. In this context, the physical, chemical and ecological water quality of the Munkulungwe Stream located on the Copperbelt of Zambia, was assessed with possible contamination from Bwana Mkubwa TSF, agriculture activities and subsequent impact on the surrounding community. The chemical and physical parameters were assessed at four sampling locations. Sampling site S1 was located on the Munkulungwe stream upstream of Bwana Mkubwa TSF, S2, S3 and S4 were on the main stream downstream of Bwana Mkubwa TSF. In addition, a macroinvertebrate composition analysis was performed to estimate the quality of water using the biotic index score. Finally, the relationship between physiochemical parameters and biotic index score was analysed to interrogate their inter-relationship with respect to water quality. The results showed that the average values of dissolved oxygen (DO) of 4.52 mg/l, turbidity (40.96 NTU), Co (0.24 mg/l), Pb (0.25 mg/l), Fe (0.36 mg/l) and Mn (0.22 mg/l) downstream exceeded international standards for drinking water. Upstream, the values of Co, Pb, Fe and Mn were within acceptable standards for drinking water, DO and turbidity were above acceptable standards. The metal concentration and total dissolved solutes were impacted by closeness to the mine tailings deposit with the heavy metal concentration being highest at S2 and S3. Moreover, high turbidity levels revealed that land erosion induced by agriculture activities is a severe problem in the area. Physical parameters were high in the rainy season due erosion escalated by rains while chemical parameters were high post rainy season. During the rainy season, the chemical contaminants are diluted and thus they are not such a big impact, but they tend to concentrate up during the dry MDNLEE001 II season. The stream at sampling points S2 and S3 was dominated by species tolerant (leech, Isopod and Snail: Pouch) and semi tolerant (Blackfly larvae and Amphipod or Scud) to pollution. The change in season influenced the composition of macroinvertebrates, with the number of species increased post rainy season. The average biotic index score (2.5) showed that the stream condition is not good, it is slightly polluted. The results showed that water quality downstream was substantially affected by Bwana Mkubwa TSF, agriculture activities and is likely to affect human health and food security. It is recommended that groundwater surrounding tailings dams should be monitored in both active and abandoned mines. Curtain boreholes around a tailings dam can be drilled and the water extracted and treated so that it doesn’t contaminate other water bodies. To improve the environmental management of mining related impacts in Zambia, mining areas should be completely rehabilitated. There is need for remediation strategies for abandoned mine sites. Constructed wetlands, roughing filtration and phytoremediation are highly promising techniques, as they are reliable, cheap, effective and sustainable. MDNLEE001 III DECLARATION I, LEE MUDENDA do here by declare that this research is my own original work and that it has not been presented and will not be presented to any other university for a similar or any other degree award. Furthermore, I declare that all secondary sources of information referred in this work have been acknowledged and referenced. Signature: Date: 05/08/2017 MDNLEE001 IV DEDICATION TO MY LATE FATHER FOR HIS ENCOURAGEMENT IN MY PURSUIT OF SUCCESS. THOUGH DEAD, YOUR VALUES AND DETERMINATION ARE ALIVE. MDNLEE001 V ACKNOWLEDGEMENTS To the Almighty GOD, am forever indebted to your love and, I am only but clay without you. Your abiding presence is the power that bids me to move on (Jeremiah 29:11-13). I am grateful to my supervisor Prof. Sue Harrison and co-supervisor Prof. Stephen Syampungani, for giving me direction and encouragements throughout my research. Special thanks go to the National Science and Technology Council (through the Strategic Research Fund programme) for the financial support that helped me to undertake my research. I remain grateful for their support. My gratitude is also extended to the African Development Bank (ADB) through CBU who facilitated my studies at the University of Cape Town. I am indebted to my loving wife Precious for the encouragement and patience, and also my children Cheempa, Chipego and Chibotu. Many thanks go to the following individuals and organizations; Nchimunya Choonya and Jhonnah Mundike, community around Munkulungwe stream and Citizens for a Better Environment (CBE) for their support. Indeed, it can be said that in the multitude of many, there is wisdom. To the Laboratory staff at the Copperbelt University, my sincere thanks for the support rendered to me, your guidance and interest during the period of study I extend my thanks to my mother, brothers and sisters for their support and prayers. I also thank all my friends and classmates, you made my studies possible through endless encouragements in good and bad times. MDNLEE001 VI Table of Contents ABSTRACT ...................................................................................................................................................... ii DECLARATION .............................................................................................................................................. iv DEDICATION .................................................................................................................................................. v ACKNOWLEDGEMENTS ................................................................................................................................ vi List of Figures ................................................................................................................................................ x List of Tables ...............................................................................................................................................xiii List of Abbreviations ................................................................................................................................... xv CHAPTER 1: INTRODUCTION ......................................................................................................................... 1 1.1 Introduction .................................................................................................................................. 1 1.2 Problem Statement ....................................................................................................................... 3 1.3 Selection of Case Study ................................................................................................................. 5 1.4 Selection of methodology ............................................................................................................. 7 1.5 Main objective .............................................................................................................................. 8 1.6 Dissertation Structure ................................................................................................................... 9 CHAPTER 2: LITERATURE REVIEW ............................................................................................................... 11 2.1 Mining and Impact on Aquatic Ecosystem .................................................................................. 11 2.1.1 Tailings dam facilities ........................................................................................................................ 12 2.1.2 Mine water problems in Zambia ....................................................................................................... 13 2.2 Mining effluents and impacts on chemical and physical parameters of aquatic ecosystems/water ................................................................................................................................... 18 2.2.1 Physical parameters .......................................................................................................................... 18 2.2.2 Chemical Parameters .......................................................................................................................
Details
-
File Typepdf
-
Upload Time-
-
Content LanguagesEnglish
-
Upload UserAnonymous/Not logged-in
-
File Pages154 Page
-
File Size-