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Final June Revisions Rule Significant Contribution Assessment TSD

This Technical Support Document (TSD) presents quantitative assessments of the relationship between the final February revisions to the Transport Rule, the final June revisions rule, and the original analysis conducted for the final Transport Rule informing the Rule’s determination of emissions that significantly contribute to nonattainment or interfere with maintenance of the National Ambient Air Quality Standards (NAAQS) in downwind states.

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