Over the last century the discharge of crude or partially treated sewage has probably been the most widespread, most documented and certainly the best understood form of pollution entering the aquatic environment. In the past two decades, however, there has been an increasing public aware­ ness of the potential hazards that exist from the contamination of the freshwater environment by toxic substances associated with the mining industry. World demand for minerals has intensified the exploitation of natural resources. In most western and newly developed countries significant mining proposals are now strenuously regulated to protect the environ­ ment. These involve economic and legislative measures and the use of appropriate control technologies. This concern will undoubtedly continue to spread worldwide requiring a programme of enlightened environmental protection management policies and practices for the future. This book has been prepared as a synthesis of our current understand­ ing of the effects of various heavy metals and acidic discharges likely to contaminate the freshwater environment as a direct result of mining activities. The review is based upon the dissertations of former BP spon­ sored students who were engaged to provide a better scientific understand­ ing of the causes of environmental problems associated with this industry. It gives us great pleasure to publish this information for use and appli­ cation by a wider audience as part of the contribution of The British Petroleum Company p.1.c. to European Year of the Environment.

1 Geological and Economic Background.- 1.1. Nickel.- 1.2. Copper.- 1.3. Zinc and lead.- 1.4. Coal.- 2 Mining Techniques and Sources of Environmental Problems.- 3 Heavy Metals in the Aquatic Environment.- 3.1. Metal speciation in freshwater systems.- 3.2. Aqueous environmental chemistry of metals.- 3.3. Transport, deposition and cycling of metals.- 3.4. Conclusion.- 4 Acid Mine Drainage in the Aquatic Environment.- 4.1. Mining and acid production.- 4.2. Factors affecting the environment.- 5 Uptake and Accumulation of Heavy Metals.- 5.1. Plants.- 5.2. Animals.- 5.3. Biological monitoring using metal accumulation.- 6 Toxicity and Tolerance to Heavy Metals. I. Plants.- 6.1. Field studies.- 6.2. Laboratory studies.- 6.3. Environmental factors affecting metal toxicity.- 6.4. Synergism, additivity and antagonism.- 7 Toxicity and Tolerance to Heavy Metals. II. Animals.- 7.1. Field studies.- 7.2. Experimental studies.- 8 Effects of Acid Mine Drainage on the Biota.- 8.1. Algae.- 8.2. Bryophytes and higher plants.- 8.3. Invertebrates.- 8.4. Fish.- 8.5. Concluding remarks.- 9 Case Study: Placer Gold Mining.- 10 Conclusions.- Appendix 1 Toxicity Tables - Plants.- Appendix 2 Sources of Published Data Used in Original Figures.- References.