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Superfund Ecological Risk Assessment 8-Step Process

In the Superfund program, Ecological Risk Assessments are done according the Ecological Risk Assessment Guidance for Superfund (ERAGS). The following diagram and table below are links to each of the eight-steps that are part of this guidance (U.S. EPA, 1997, Ecological Risk Assessment Guidance for Superfund: Process for Designing and Conducting Ecological Risk Assessments, Interim Final, EPA 540-R-97-006. For more details on any of these steps beyond what is presented on this website, click above to download guidance document).

Steps 1 & 2 are considered to be part of the Screening Level Ecological Risk Assessment

1. Screening-level problem formulation and toxicity evaluation

  • Problem formulation - information is gathered about the site
  • Site visit - investigators visit the site
  • Ecological effects evaluation - review of scientific literature to determine at what levels the chemicals present will have adverse effects
  • Estimating exposures - calculating how much plants and animals are exposed to chemicals at the site;
  • Risk calculation - calculation of Hazard Quotients--the comparison of the levels of chemical contamination at the the site to levels that are known to cause harm
Steps 3 to 7 are considered to be part of the Baseline Ecological Risk Assessment
  • Refining Contaminants of Potential Ecological Concern (COPECs) - deciding whether or not chemicals found at the site should be considered further in determining potential ecological risk
  • Contaminant fate and transport - what happens to the chemicals, biologically, chemically, physically and how they move among plants and animals
  • Mechanisms of toxicity - what are the harmful effects on plants and animals
  • Ecosystems potentially at risk - habitats and plants and animals present; sensitivity by plants and animals to chemicals; water bodies present
  • Exposure pathways - how the chemicals pass through the food web from the source of contamination
  • Assessment endpoints - the characteristic(s) of a plant or animal that can be measured in terms of harmful effects
  • Conceptual site model - collection of exposure pathways
  • Risk questions - using various lines of evidence, answer the question "does chemical X cause harmful effects in plant or animal Y?"
  • Work plan and sampling plan - a written description of how the investigation will proceed at the site
  • Measurement endpoints - what is measured (i.e., reproduction, mortality, growth, etc.) in relationship to the assessment endpoints
  • Study design - what type of testing will be done to evaluate the potential ecological risk at the site
  • Data quality objectives and statistical considerations - a series of planning steps to insure the quality, type, and quantity of data will be adequate and defendable
  • Determining if the site conditions still allow the investigation to proceed as described in Step 4 or if new conditions require modifications of the work plan.
  • Site investigation - the work as described in the work plan is carried out
  • Data analysis - the information gathered is analyzed according to the work plan and statistical design
  • Risk estimation and characterization - combining the results of the studies performed to produce an estimate of the ecological risk and describe that risk in terms of extent, future potential for risk, how long might contamination remain, and what are the prospects of natural recovery if no action is taken
  • Decisions are made concerning what future actions, if any, are to be undertaken.

* These steps are followed by a Scientific Management Decision Point (SMDP), during which it is decided upon appropriate future courses of action, if any.

Figure 1. Schematic Diagram of the Superfund Eight-Step Ecological Risk Assessment (ERA) Process

Note: the diagram is an image map. Click on different parts to go to separate pages on each step. (If the image map does not load, click the 'reload' button on your browser.)


Diagram of Ecological Risk Assessment 8-step process

Note: SMDP is the abbreviation for "Scientific Management Decision Point"; these are points in the Ecological Risk Assessment process when the site project manager and scientific advisors decide upon what additional steps, if any, are necessary to take.

Link to ERA Step 1 Link to ERA Step 2 Link to ERA Step 3 Link to ERA Step 4 Link to ERA Step 5 Link to ERA Step 6 Link to ERA Step 7 Link to ERA Step 8 Link to Step 3 SMDP Link to Step 4 SMDP Link to Step 5 SMDP Link to Step 6 SMDP Link to Step 7 SMDP Link to Step 8 SMDP Link to Step 2 SMDP

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