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Environmental Geotechnics ENVIRONMENTAL GEOTECHNICS Edited by International Technical Committee No. 5 (ITC5) on Environmental Geotechnics of the International Society of Soil Mechanics and Geotechnical Engineering (ISSMGE) First Edition: September 2005 Second Edition: June 2006 TC5 Report, June 2006 CONTENTS PREFACE Chapter 1. DESIGN BASICS AND PERFORMANCE CRITERIA Task Force Leader: R. CLARK (United Kingdom) 1.1 Terminology, definitions and units 1.2 Multidisciplinary interactions 1.2.1 General 1.2.2 Terminology 1.2.3 Input of other disciplines into environmental geotechnics 1.2.4 Interaction with regulators 1.2.5 Interaction with non-technical people 1.2.6 Education 1.2.7 Concluding remarks 1.3 Classification and characterization 1.3.1 General 1.3.2 Soil and soil properties 1.3.3 Chemicals and chemical properties 1.3.4 Contaminated land 1.3.5 Geosynthetics 1.3.6 Waste materials 1.4 Risk assessment 1.4.1 Principles and application to environmental geotechnics 1.4.2 Groundwater pollution 1.4.3 Gas migration 1.4.4 Reliability 1.4.5 Further work 1.5 Monitoring 1.5.1 Introduction 1.5.2 Non-intrusive methods 1.5.3 Intrusive Methods 1.5.4 Guidelines for monitoring design 1.5.5 Monitoring performance criteria 1.5.6 Monitoring of landfills 1.5.7 Monitoring of contaminated land (as part of investigations) 1.5.8 Monitoring of Remediation (during treatment and post treatment) 1.5.9 Monitoring of containment barriers 1.5.10 Quality assurance 1.5.11 Concluding remarks i TC5 Report, June 2006 1.6 Lifetime of components 1.6.1 Introduction 1.6.2 Compacted Clay Liners 1.6.3 Bentonite Enhanced Soils 1.6.4 Geosynthetic Clay Liners 1.6.5 Geomembrane Liners 1.6.6 In Ground Cut-off Barriers 1.6.7 Landfill Drainage Layers 1.7 Quality assurance and control 1.7.1 Principles 1.7.2 Quality Assurance Plan(s) 1.7.3 QA Personnel 1.7.4 QC Personnel 1.7.5 QA for Landfill Containment 1.7.6 QA for Contamination Remediation 1.7.7 Final Certificate and Validation Report Chapter 2. MANAGING CONTAMINATED SITES Task Force Leader: S. JEFFERIS (United Kingdom) 2.1 Introduction 2.1.1 Environmental risk and the geotechnical engineer 2.1.2 The presence of contamination on a site 2.1.3 The role of the geotechnical engineer in contaminated land management 2.2 The perception of pollution 2.2.1 Some questions 2.2.2 Environmental audits and assessments 2.3 General structure of contaminated land legislations 2.3.1 The enforcing Agency 2.3.2 Legislative control levels 2.3.3 Risk and harm 2.3.4 Liability for contaminated land 2.4 Assessment of the site 2.4.1 Source and type of contamination 2.4.2 Geology and hydrogeology 2.4.3 Overall checklist 2.5 Considerations for remedial design and implementation 2.5.1 Isolation or containment 2.5.2 In-situ treatment 2.5.3 Pump and treat techniques 2.5.4 On-site, ex-situ soil cleaning 2.5.5 Natural attenuation 2.5.6 Summary on remediation processes 2.5.7 Insurance ii TC5 Report, June 2006 2.5.8 The regulator 2.6 Risks and risk based methodologies 2.6.1 Risk analysis as a starting point 2.6.2 Risk and harm 2.6.3 Types of risk from contaminated land 2.6.4 Key questions 2.6.5 Check list for source-pathway-receptor analysis 2.7 Computer based risk analysis models 2.8 Wider considerations 2.8.1 Extension to hazards other than human health 2.9 Methodologies for developing countries 2.10 Ireland - current state of remediation 2.10.1 Background 2.10.2 Key sites 2.10.3 Guidelines 2.10.4 Present strategies 2.11 Summary Chapter 3. TRADITIONAL AND INNOVATIVE BARRIERS TECHNOLOGIES AND MATERIALS Task Force Leader: C.D. SHACKELFORD (USA) PART I – TRADITIONAL BARRIERS 3.1 Traditional liners and liner materials 3.1.1 Compacted clay liners 3.1.2 Geosynthetic clay liners 3.1.3 Composite barriers 3.2 Traditional covers and cover materials 3.2.1 Compacted clay covers 3.2.2 Composite covers 3.2.3 Geosynthetic clay liners PART II – INNOVATIVE BARRIERS 3.1 Introduction 3.2 Innovative covers and cover materials 3.2.1 Alternative earthen final covers 3.2.2 Exposed geomembrane covers 3.2.3 Geochemical covers 3.2.4 Covers from pulp and paper mill sludge 3.3 Innovative liners and liner materials 3.3.1 Reactive liners and barriers 3.3.2 Geochemical barriers 3.3.3 Biobarriers 3.3.4 Asphaltic barriers 3.3.5 Glass liners iii TC5 Report, June 2006 3.3.6 Clay membrane barriers 3.3.7 Residual soil liners 3.3.8 Chemically stabilized clay liners 3.3.9 Polymer gel barriers Chapter 4: UNDERWATER GEOENVIRONMENTAL ISSUES Task Force Leader: M. KAMON (Japan) 4.1 General view of underwater problems 4.2 Basic characteristics of the underwater materials 4.3 Dredging operations 4.4 Dredging and clean-up underwater materials 4.5 Spillage water treatment 4.6 Odor control 4.7 Containment and isolation 4.7.1 Confined disposal facility 4.7.2 Sludge containment structure 4.7.3 Environmental impact from cdf 4.8 Remediation of contaminated sludge 4.9 Beneficial uses of dredged materials 4.9.1 Case study of land use 1: dewatering method 4.9.2 Case study of land use 2: Ketelmeer project 4.9.3 Reuse of dredged materials 4.10 Conclusions Chapter 5. SEISMIC DESIGN OF SOLID WASTE LANDFILLS AND LINING SYSTEMS Task Force Leader: P. SECO E PINTO (Portugal) 5.1 Introduction 5.2 Performance of solid waste landfills during earthquakes 5.3 Analysis of solid waste landfills stability during earthquakes 5.3.1 Introduction 5.3.2 Experimental methods 5.3.3 Mathematical methods 5.3.4 Selection of design earthquakes 5.3.5 Selection of soil properties for dynamic analysis 5.3.6 Seismic response analysis 5.3.7 Liquefaction assessment 5.4 Dynamic response of geomembrane liners 5.4.1. Introduction 5.4.2. Dynamic geosynthetic interface behaviour iv TC5 Report, June 2006 5.4.3. Predicting landfill response 5.4.4. Dynamic response of geomembrane base liner 5.4.5. Dynamic response of geomembrane cover liner 5.4.6. Stability analysis during and after seismic loading 5.5 Monitoring and safety control of landfills 5.6 Safety and risk analyses 5.7 Final remarks Chapter 6. EDUCATION IN ENVIRONMENTAL GEOTECHNICS Task Force Leader: M. MANASSERO (Italy) 6.1 Introduction 6.2 From traditional soil mechanics to environmental geotechnics education 6.3 Basic contents of environmental geotechnics 6.4 University educational programs in environmental geotechnics 6.4.1 University education programs in North America 6.5 Summary Chapter 7. NUCLEAR WASTE Task Force Leader: A. GENS (Spain) 7.1 Introduction 7.2 Nuclear processes and nuclear waste 7.2.1 Nuclear processes and radioactivity 7.2.2 Sources and types of nuclear waste 7.3 Disposal of high level nuclear waste 7.3.1 Disposal strategies 7.3.2 Fundamentals of deep geological disposal 7.3.3 Multi-barrier concept 7.3.4 Host rocks 7.4 Construction of a deep geological repository 7.4.1 Site investigation and construction 7.4.2 Excavation damaged zone and excavated disturbed zone 7.5 Performance and safety assessment 7.5.1 Quantitative safety demonstration 7.5.2 Processes in the engineered barrier and near field 7.5.3 Processes in the natural (geological) barrier 7.5.4 Safety assessment result 7.5 Disposal of low and intermediate level nuclear waste 7.6 Remediation of uranium mining sites 7.7 Final remarks v TC5 Report PREFACE This report has been generated as part of the activities of International Technical Committee No. 5 (ITC5) on Environmental Geotechnics of the International Society of Soil Mechanics and Geotechnical Engineering (ISSMGE) during the period 2001-2005. The primary aim in generating this report is to provide an overview of the state-of-the-art and the state-of-practice pertaining to three main areas of environmental geotechnics, viz., waste disposal by landfills, remediation of contaminated soils and underwater geoenvironmental issues. All three of these topics are considered from both scientific and technical points of view, and are covered for the purpose of both practitioners and researchers working in the field of environmental geotechnics, as well as individuals in other professional areas (e.g., chemical engineering, environmental engineering) who desire a comprehensive, yet relatively concise, overview of the field of environmental geotechnics. The report describes the roles and functions of the fundamental components required for safe disposal of polluting materials or remediation of polluted lands from the standpoint of design, control and management. Attention also is given to research currently in progress that is devoted to improving our knowledge of design parameters significantly influencing the performance of modern landfill containment systems. The introduction and, in some cases, reintroduction of performance-based design as a more desirable approach relative to prescribed or regulated design and its increasing acceptance by the geoenvironmental community has led to a rethinking of how the design of containment systems should be approached. With the trend towards performance- based design, the design engineer must take into account numerous parameters, including contaminant transport parameters and the service life of clay (mineral) barriers, drainage layers, geosynthetics, and the main features of the waste in order to be able to estimate the leachate quality and production over the landfill activity and post-closure periods. Today, most of these parameters are rather readily assessable, whereas others are presently being investigated through research programs and, therefore, still are not considered fully reliable.
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