
266 Environmental Impact Analysis
Risk but extent
uncertain
Detailed ecological investigation
design and implementation
Revised & detailed problem
formulation
Risk
characterization
Input to remediation decisions
Initial problem formulation
including ecological endpoints
Screening level exposure estimate and risk
characterization
No elevated
risk
Signif icant and
extensive risk
Exposure
characterization
Eects
characterization
FIGURE 7.1
An ecological risk assessment process summary. (Adapted from U.S. EPA. 1997. Ecological
risk assessment guidance for Superfund: Process for designing and conducting ecological risk
assessments: EPA 540-R-97-006; U.S. ...