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Visibility and Haze

Draft Guidance for the Second Implementation Period of the Regional Haze Rule

This draft guidance document was prepared by the EPA to assist states in developing and submitting regional haze State Implementation Plans for the second implementation period (2018-2028). This document is currently in draft form, and the EPA plans to finalize the guidance after the public comment period. The availability of this draft guidance and the details of the public comment period are announced in the Notice of Availability. A summary of the purpose and content of the document is given in the fact sheet.

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