Table of Contents

Introduction: Definitions and Concepts
Scope and Definitions
Regulatory Context
Ecorisk Framework
The Remedial Process
Site Characterization and Scoping Assessment
The Assessment Planning Process
The Assessment Plan
Baseline Ecological Risk Assessment
Remedial Alternatives Assessment
Efficacy Assessment
Damage Assessment
Tiers: Scoping, Screening, and Definitive Assessments
Relationship to Human Health Risk Assessment
Differences in Human Health and Ecological Risk Assessment
Why Ecological Endpoints May be More Sensitive than Humans
Scale in Human Health and Ecological Risk
Participants in Ecological Risk Assessments
Problem Formation
Risk Managers and Risk Assessors
Physical Scope
Spatial Extant
Spatial Units
Source Units
Watershed Units
Groundwater Units
Terrestrial Integrator Units
Spatial Subunits
Site Description
Source Description
Assessment Endpoints Selection
Selection of Endpoint Properties
Selection of Levels of Effect on Properties of Endpoint Entities
Conceptual Models
Conceptual Models of Alternative Baseline Scenarios
Components of a Conceptual Model
Unit Types and Default Conceptual Models
Sources
Routes of Transport
Exposure Media
Receptors
Indirect Exposure and Effects
Output to Other Units
Relationship to Other Conceptual Models
Form of the Conceptual Model
Analysis Plan
Measures of Exposure, Effects, and Environmental Conditions
Sampling and Analysis Plan
Reference Sites and Reference Information
Field Verification of the Plan
Deviations and Contingencies
Analysis of Exposure
Components of Analysis of Exposure
Sampling and Chemical Analysis of Media
Chemical Analysis of Biota and Biomarkers
Bioassay
Biosurvey
Transport and Fate Models
Exposure Models
Exposure to Contaminants in Surface Water
Exposure to Contaminants in Soil
Sampling, Extraction, and Chemical Analysis
Partial Chemical Extraction and Normalization
Nonaqueous Phase Liquids
Soil Depth Profile
Future Exposure
Exposure of Aquatic Organisms
Exposure of Plants
Rooting Depth
Rhizosphere
Wetlands
Soil Properties
Chemical Form
Chemical Interactions
Interspecies Differences
Air as an Exposure Route
Exposure of Soil Invertebrates
Depth of Exposure and Ingested Material
Soil Properties and Chemical Interactions
Exposure of Soil Microbial Communities
Exposure of Wildlife
Exposure Based on Internal Measures
Exposure Based on External Measures
Parameters for Estimation of Exposure
Uptake Models
Aquatic Organism Uptake
Terrestrial Arthropod Uptake
Terrestrial Vertebrate Uptake
Petroleum and Other Chemical Mixtures
Summary of Exposure Characterization
Screening Against Ecotoxicological Benchmarks
Exposure Concentrations
Screening Media
Screening Receptors
Screening Sites
Data Collection and Evaluation
Data Adequacy and Uncertainties
Presentation of a Screening Assessment
Risk Characterization: Definitive
Single Chemical Toxicity
Aqueous Exposure of Aquatic Organisms
Sediment Exposure of Benthic Invertibrate
Soil Exposure of Plants, Invertebrates and Microbial Communities
Multi-Media Exposure of Wildlife
Body Burdens of Endpoint Organisms
Ambient Media Toxicity Tests
Biological Surveys
Biomarkers
Weight of Evidence
Triad Alternatives
Future Risks
Interpretation
Reporting Ecological Risks
Uncertainty
Concepts and Definitions
Why Analyze Uncertainty?
Quantitative Techniques for Analysis of Uncertainty
Making Sense of Uncertainty and Probability
Methods for Exposure
Methods for Effects
Methods for Risk Characterization
Parameters to Treat as Uncertain
Remedial Goals
Preliminary Remedial Goals
Prigs for Surface Water
Sediment
Soil
Modification of PRGs
Land Use
Remedial Goal Options
Human Health
Remedial Decisions
Risks From Remediation
Problem Formulation
Conceptual Models for Alternatives Assessment
Assessment Endpoints
Exposure and Effects Assessment
Case Studies
Recovery
Time to Recovery
Hastening Recovery
Balancing Risks
Different Risk Metrics
Win/Lose Outcomes
Land Use Conflicts, Etc.
Cost-Benefit Analysis
Post-Remedial Assessment
Post-Remedial Monitoring
Residual Risks
Preassessment Screen Phase
Assessment Plan Phase
Assessment Phase
Quantification Phase
Damage Determination
Post-Assessment Phase
Alternative Approaches
Conclusions
Glossary
Appendix
References