In the USA, Western and Central Europe, there are many large-scale polluted sites that are too large to be cleaned up economically with available technologies. The pollution is caused by mining activities, smelters and other heavy industries, not only to soils, but also to sediments in waterways and reservoirs. New sites are also being created with little concern for environmental protection. Since these areas are expected to remain polluted for many years, it is necessary to take a long-term view to insure that the capacity to retain the contaminants is not diminished and to understand the potential for large-scale contaminant mobilization at these sites triggered by changing environmental conditions. Therefore, the soil-sediment system as a dynamic entity can be described as biogeodynamics, since a full understanding of long-term changes requires the combination of the "geo" and "bio" sciences. This book provides information for predicting long-term changes and making risk assessments and describes the approach of geochemical engineering to handling large-scale polluted sites.

Inhalt

1 Long-term Strategies for Handling Contaminated Sites and Large-scale Areas.- 1.1 Introduction.- 1.2 Time Frames: Soils and Sediments as Part of the Hydrologicai Cycle.- 1.3 Conceptual Framework for Understanding Long-term Processes in Soils and Sediments.- 1.4 Long-term Changes: Capacity Controlling Parameters.- 1.5 Case Studies.- 1.6 Summary and Conclusions.- 2 Microbiology of Soil and Sediments.- 2.1 Introduction.- 2.2 Microbial Environment of Soil and Sediment.- 2.3 Degradation of Xenobiotics in Soil and Sediment.- 2.4 Interaction of Heavy Metals and Micro-organisms.- 2.5 Concluding Considerations in Relation to Risk Assessment.- 3 Heavy Metal Retention by Soil Organic Matter under Changing Environmental Conditions.- 3.1 Introduction.- 3.2 The Cycling of SOM.- 3.3 Interactions between SOM and Heavy Metals.- 3.4 Heavy Metal Interactions with Soil Biota.- 3.5 CTB Risks Associated with Heavy Metal Retention in SOM.- 3.6 Conclusions and Final Remarks.- 4 Mobilization of Heavy Metals as Affected by pH and Redox Conditions.- 4.1 Introduction.- 4.2 The Chemistry of Natural Waters.- 4.3 pH and Redox Related Processes Controlling the Solubility of Heavy Metals.- 4.4 Environmental Changes Causing pH and Redox Variations.- 4.5 Sensitive Environments.- 4.6 Summary and Conclusion.- 5 Erosion and Transport of Pollutants from the Terrestrial to the Aquatic Environment.- 5.1 Introduction.- 5.2 Soil Erosion and Delayed Non-linear Responses.- 5.3 Long-term Changes Soil Properties.- 5.4 Some Examples of Potential Non-linear Delayed Responses.- 5.5 Conclusions.- 6 Long-term Fate of Pesticides in Soil.- 6.1 Introduction.- 6.2 Behaviour and Fate of Pesticides in Soil.- 6.3 Pesticide Residues in Soil.- 6.4 Remobilization Potentials of Pesticide Residues in Soils.- 6.5 Conclusions.- 7 Regional Differences in Potentials for Delayed Mobilization of Chemicals in Europe.- 7.1 Introduction.- 7.2 Loads and Loadings.- 7.3 Regional Differences in Storage Capacity in Soils.- 7.4 Delayed Effects due to Changes in Storage Capacity of Soils: Examples.- 7.5 Summary.- 8 Capacity Controlling Parameters and Their Impact on Metal Toxicity in Soil Invertebrates.- 8.1 Introduction.- 8.2 Toxicity Tests and Routes of Exposure in Soil.- 8.3 The Influence of Soil Properties on the Toxicity of Heavy Metals for Soil Invertebrates.- 8.4 The Influence of Soil Properties on the Bioaccumulation of Heavy Metals in Soil Invertebrates.- 8.5 Discussion and Conclusions.- 9 Acidification and its Long-term Impact on Metal Mobility.- 9.1 Introduction.- 9.2 Some Basic Geographical Data on Poland.- 9.3 Acidification of the Environment.- 9.4 Soil Conditions: Vulnerability.- 9.5 Heavy Metals.- 9.6 Effects on Humans.- 9.7 What May Happen with Heavy Metals Accumulated in the Soils?.- 9.8 Concluding Remarks.- 10 Mercury and the New Gold Rush in the South.- 10.1 Introduction.- 10.2 Mercury Use in Gold- and Silver-mining and its Dispersal Mechanisms in Aquatic Systems.- 10.3 Mercury Distribution in Aquatic Sediments in Gold-mining Areas.- 10.4 Mercury Distribution in Soils.- 10.5 Atmospheric Dispersal.- 10.6 Mercury Methylation.- 10.7 Mercury in Fishes.- 10.8 Contamination in Humans.- 10.9 Technologies for Cleaning Up Mercury Contaminated Areas.- 10.10 Conclusions and Outlook.- 11 Non-linear Release of Metals from Aquatic Sediments.- 11.1 Introduction.- 11.2 Geochemical Concepts for Metallic Pollutants in Sediments.- 11.3 Redox/pH-Reactions: Variations in Time and Space.- 11.4 Influence of Redox Variations of Metal Mobility in Sediments.- 11.5 Implications on Sediment Quality Criteria Assessment.- 11.6 Remediation Procedures.- 11.7 Summary and Outlook.- 12 How to Manage Accumulated Contaminants.- 12.1 Introduction.- 12.2 Contamination Pattern.- 123 Biogeochemical Processes as Management Tools.- 12.4 Supplementing the System to Increase the Immobilization Capacity.- 12.5 Managing Environmental Impacts in Changed Land-use and Soil Management Systems.- 13 Global Perspectives and Risk Assessment.- 13.1 Introduction.- 13.2 Land as a Receptor and Emitter of Environmentally-Harmful Chemicals.- 13.3 Cadmium Pollution in Agricultural Soils of the Rhine Basin: A Practical Example.- 13.4 The Impact Of Conversion Of Agricultural Land.- 13.5 Management Options.