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Reviewing National Ambient Air Quality Standards (NAAQS)

Sulfur Dioxide (SO2) Standards - Policy Assessments from Current Review

The policy assessment (PA) presents a staff analysis of the scientific basis for policy options for consideration by senior EPA management prior to rulemaking. Such an evaluation of policy implications is intended to help ‘‘bridge the gap’’ between the Agency’s scientific assessments, presented in the integrated science assessment (ISA) and risk/exposure assessment (REA), and the judgments required of the EPA Administrator in determining whether it is appropriate to retain or revise the NAAQS.

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