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Risk Assessment

Regional Ecological Risk Assessment (ERA) Supplemental Guidance

This guidance was developed by the U.S. Environmental Protection Agency (EPA) Region 4 Superfund Division’s Scientific Support Section (SSS) risk assessment staff to update and replace all Region 4 Ecological Risk Assessment Supplemental Guidance and to supplement Agency guidance documents on site-specific Ecological Risk Assessment: Guidelines for Ecological Risk Assessment (GERA; EPA, 1998) published by the Risk Assessment Forum provides agency-wide guidance. This supplemental guidance clarifies the National ERAGS guidance as interpreted and applied to Region 4.

This supplemental guidance provides direction and does not constitute rulemaking by the Agency. The intent of this guidance is to aid in the development of high-quality risk assessments consistent with the expectations of the SSS in its oversight role.

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