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Risk Assessment

Tier 3 Toxicity Value White Paper

The purpose of this white paper is to articulate the issues pertaining to Tier 3 toxicity values and provide recommendations on processes that will improve the transparency and consistency of identifying, evaluating, selecting, and documenting Tier 3 toxicity values for use in the Superfund and Resource Conservation and Recovery Act (RCRA) programs. This white paper will be used to assist regional risk assessors in selecting Tier 3 toxicity values as well as provide the foundation for future regional and national efforts to improve guidance and policy on Tier 3 toxicity values.

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  • Tier 3 Toxicity Value White Paper (PDF)(19 pp, 6 MB)
    The purpose of this white paper is to articulate the issues pertaining to Tier 3 toxicity values and provide recommendations on processes that will improve the transparency and consistency of identifying, evaluating, selecting, and documenting Tier 3 toxic