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Risk Assessment

Risk Assessment Guidance for Superfund (RAGS) Volume III: Part A

Risk Assessment Guidance for Superfund Volume III: Part A (RAGS: Volume 3A) provides policies and guiding principles on the application of probabilistic risk assessment (PRA) methods to human health and ecological risk assessment in the U.S. Environmental Protection Agency (EPA) Superfund program. Volume 3A supplements existing human health and ecological assessment guidance provided in the RAGS series. Volume 3A builds upon basic concepts of risk assessment outlined in RAGS Volume I (U.S. EPA, 1989a; 2001), recent guidance for Ecological Risk Assessment (U.S. EPA, 1992, 1994, 1997a, 1998a; 1999), and the Agency Probabilistic Analysis Policy document (U.S. EPA, 1997b).

Volume 3A focuses on Monte Carlo analysis as a method of quantifying variability and uncertainty in risk. This guidance was developed by the Superfund PRA Workgroup and the Ecological Risk Assessment Forum (RAF); both are intra-Agency workgroups that have focused on improving the Risk Assessment Guidance for Superfund and implementing Superfund Reform activities. This guidance introduces a tiered approach to PRA, beginning with a point estimate analysis and progressing to increasing levels of complexity until the scope of the analysis satisfies decision-making needs.

Volume 3A is intended to be most accessible to those readers who are familiar with risk assessment and basic statistical concepts. Potential users of this guidance include risk assessors, risk managers, and other decision makers responsible for conducting and reviewing PRA, or communicating PRA concepts and results.

RAGS Volume 3A Guidance Document

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