Ecological Risk Assessment

In a multi-part blog series this installment examines the ecological risk assessment process.  However, keep in mind that this process should be accompanied by a human health risk assessment and followed by appropriate risk management measures.

The US Environmental Protection Agency (EPA) has identified an eight (8) step process for conducting an ecological risk assessment at a Superfund site.

Step 1: Screening-level problem formulation and toxicity evaluation

• Problem formation
• Site visit
• Ecological effects evaluation

Step 2: Screening-level exposure estimate and risk calculation

• Estimating exposures
• Risk calculation

Step 3: Problem formulation

• Refining Contaminants of Potential Ecological Concern (COPECs)
• Contaminant fate and transport
• Mechanisms of toxicity
• Ecosystems potential at risk
• Exposure pathways
• Assessment endpoints
• Conceptual site model
• Risk questions

Step 4: Study design and data quality objectives process

• Work plan and sampling plan
• Measurement endpoints
• Study design
• Data quality objectives and statistical considerations

Step 5: Field sampling plan verification


Step 6: Site investigation and data analysis

• Site investigation
• Data analysis

Step 7: Risk characterization

• Risk estimation and characterization

Step 8: Risk management


Ecological risk assessments are completely necessary to understand the site impacts to the environment.