Contaminated Land Management: Ready Reference Contents PART A SITE ASSESSMENT SECTION 1 CONCEPTUAL MODELS 1.1 The nature of conceptual models 1.1.1 The nature of conceptual models 1.2 Worked examples of conceptual models 1.2.1 Example conceptual model for a Phase 1 risk assessment 1.2.2 Example conceptual model for a Phase 2 risk assessment 1.3 Significant pollution linkages 1.3.1 Significant pollutant linkages 1.3.2 Categories of significant harm 1.3.3 Significant possibility of significant harm SECTION 2 PHASE 1s 2.1 Desk studies 2.1.1 Information required for desk studies 2.1.2 Ordnance Survey maps2.1.3 Features of geological formations in the UK relevant to contaminated land 2.1.4 Groundwater and surface water classifications 2.1.5 List of industry profiles published by DoE (now DEFRA) 2.1.6 Schedule of contaminative uses 2.2 Walkover 2.2.1 Walkover surveys 2.2.2 Field checklist of information to record during walkover surveys to identify potential sources of contamination 2.2.3 Field checklist of information to record during walkover surveys to plan site investigation 2.2.4 Possible meanings of odours and colours encountered during walkover surveys SECTION 3 SAMPLING STRATEGY 3.1 Soil sampling strategy3.1.1 Soil sampling strategies 3.1.2 Non-targeted sampling to detect hotspots 3.1.3 Ready reckoner for calculating number of non-targeted samples 3.1.4 Sampling stockpiles 3.2 Groundwater sampling/monitoring strategies 3.2.1 Groundwater sampling and monitoring strategies 3.3 Gas sampling/monitoring strategies 3.3.1 Ground gas and vapour monitoring strategies SECTION 4 METHODS OF INVESTIGATION 4.1 Safety, health and environment 4.1.1 Safety, health and environment (SHE) 4.1.2 BDA/Site Investigation Steering Group site categorisation system for safe investigation of contaminated land 4.2 Geophysics 4.2.1 Geophysics 4.2.2 Uses of geophysics: determine extent of features relevant to contamination 4.2.3 Uses of geophysics: locate buried objects 4.2.4 Uses of geophysics: investigate groundwater 4.2.5 Uses of geophysics: investigate geology (including man-made features) 4.3 Intrusive investigation 4.3.1 Shallow samples – for human health risk assessment 4.3.2 Trial pits 4.3.3 Probeholes 4.3.4 Boreholes: cable percussion 4.3.5 Boreholes: rotary cored or open hole 4.3.6 Decontamination of equipment 4.4 Field tests 4.4.1 Field tests 4.4.2 Headspace tests 4.5 Groundwater investigation techniques 4.5.1 Constructing groundwater monitoring installations in boreholes 4.5.2 Groundwater monitoring and sampling 4.6 Gas investigation techniques 4.6.1 Constructing gas monitoring installations in probeholes 4.6.2 Constructing gas monitoring installations in boreholes 4.6.3 Gas monitoring and sampling 4.7 Soil and rock description 4.7.1 Soil description 4.7.2 Rock description 4.8 Sample handling/preservation 4.8.1 Sample handling and preservation 4.9 Laboratory analysis 4.9.1 Laboratory analysis 4.9.2 Grouping of chemical compounds: organics 4.9.3 Grouping of chemical compounds: inorganics 4.9.4 List I and II substances 4.9.5 Bioaccessibility tests with respect to soil ingestion by humans 4.10 Outline costs 4.10.1 Guideline site investigation costs 4.11 Describing data 4.11.1 Describing data 4.11.2 Estimating the representative contaminant concentration (population mean u) to a defined confidence level SECTION 5 RISK ASSESSMENT 5.1 The four stages of risk assessment 5.1.1 Risk assessment 5.2 Generic assessment criteria 5.2.1 Guideline values for soil 5.2.2 Interdepartmental Committee on the Redevelopment of Contaminated Land (ICRCL) guideline values 5.2.3 Dutch guideline values 5.2.4 US soil screening levels (SSLs) 5.3 Site specific risk assessment tools for human health 5.3.1 Principles of determining site specific human health risk assessment (HHRA) criteria 5.3.1.1 Site investigation input requirements for human health risk assessment (HHRA) 5.3.1.2 Toxicological inputs 5.3.1.3 Physico-chemical properties of contaminants 5.3.1.4 Identifying and characterising the critical receptor 5.3.1.5 Exposure pathways 5.3.1.5.1 Soil ingestion exposure pathway 5.3.1.5.2 Vegetable consumption exposure pathway 5.3.1.5.3 Inhalation of soil vapours outdoors exposure pathway 5.3.1.5.4 Inhalation of soil vapours indoors exposure pathway 5.3.2 Human health risk assessment tools 5.3.2.1 SNIFFER 2000 5.3.2.2 RBCA (Risk Based Corrective Action) 5.3.2.3 RiscHuman 5.3.2.4 Risk*Assistant 5.3.2.5 CLEA 2002 5.3.3 Uncertainty in human health risk assessment 5.4 Risk assessment for groundwater 5.4.1 Groundwater risk assessment 5.4.2 Methodology for derivation of remedial targets for soil and groundwater to protect water resources 5.4.2.1 Preliminary assessment of risk for groundwater 5.4.2.2 Tier analysis for soil to derive remediation target concentrations for water resources protection 5.4.2.3 Tier analysis for groundwater to derive remediation target concentrations for water resources protection 5.4.3 Water quality standards 5.4.4 ConSim contamination impact on groundwater: simulation by Monte Carlo Method 5.5 Risk assessment for gas 5.5.1 Risk assessment for gases 5.5.2 Some current guideline values for gases 5.5.3 Descriptors for some factors considered when classifying gassing sites 5.5.4 Characteristic situations developed by Wilson and Card (1999) 5.5.5 GasSim 5.6 Risk assessment for ecology 5.6.1 Risk assessment for ecology 5.7 Risk assessment for buildings 5.7.1 Risk assessment for buildings 5.8 Risk assessment for property 5.8.1 Risk assessment for property PART B RISK MANAGEMENT SECTION 6 INTRODUCTION TO AND CLASSIFICATION OF RISK MANAGEMENT TECHNIQUES 6.1 Introduction to and classification of risk management techniques 6.1.1 Remedial measures in overview 6.1.2 Fundamental concepts for classification of risk management techniques 6.1.3 Simplified outline of treatment based options 6.1.4 Civil engineering based methods 6.1.5 Physical/chemical treatment options 6.1.6 Biological treatment options 6.1.7 Solidification/stabilisation treatment options 6.1.8 Thermal treatment options 6.1.9 Remediation to protect development from hazardous gases SECTION 7 RISK MANAGEMENT TECHNIQUES 7.1 Civil engineering techniques for soil, groundwater and gas 7.1.1 Excavation and related materials handling 7.1.2 Disposal of contaminated soil 7.1.3 Infilling void 7.1.4 Cover systems 7.1.5 Vertical barriers 7.2 In situ treatment technologies for soil and groundwater 7.2.1 Soil vapour extraction (SVE) and bioventing: also called soil venting or soil vacuum extraction 7.2.2 Air sparging and biosparging 7.2.3 In situ flushing: also known as in situ soil washing 7.2.4 Pump and treat (P & T) 7.2.5 Permeable reactive barriers 7.2.6 Redox amendments for enhanced bioremediation 7.2.7 In situ oxidation techniques 7.2.8 Electro-remediation 7.2.9 Phytoremediation 7.2.10 Monitored natural attenuation: also known as intrinsic bioremediation 7.3 Predominantly ex situ treatment technologies for soil and groundwater 7.3.1 Ex situ bioremediation 7.3.2 Soil washing and related ex situ treatments 7.3.3 Solidification/stabilisation processes: the combined process of solidification/stabilisation may be referred to as fixation 7.3.4 Thermal treatments 7.3.5 Vitrification 7.3.6 Ex situ groundwater and vapour treatment 7.4 Remediation to protect development from hazardous gases 7.4.1 Dilution and dispersion of gases in-ground 7.4.2 Gas barriers in-ground 7.4.3 Dilution and dispersion of gases for buildings 7.4.4 Gas barriers for buildings 7.4.5 Long-term post construction monitoring for gases SECTION 8 REMEDY SELECTION AND OUTLINE COSTS 8.1 Remedy selection 8.1.1 Framework for considering remedial measures 8.1.2 Simplified treatment technologies screening matrix 8.1.3 Indicative costs 8.1.4 Sustainable development and contaminated land remediation PART C APPENDICES SECTION 9 USEFUL INFORMATION 9.1 Useful information 9.1.1 Ordnance Survey abbreviations 9.1.2 Some useful conversions 9.1.3 Example hydrocarbon structures 9.1.4 Geological time scale 9.2 Statistical tables 9.2.1 Percentage points of the normal distribution 9.2.2 Percentage points of the Student t distribution 9.2.3 Values of H for computing 95% UCL on a lognormal mean 9.3 Websites 9.3.1 Websites |