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Visibility and Haze

Guidance on Regional Haze State Implementation Plans for the Second Implementation Period

August 20, 2019 -- EPA issued guidance to assist states as they develop plans to address visibility impairment for the second implementation period under EPA’s Regional Haze Rule. This is one of a series of implementation tools and guidance documents that will help focus states’ efforts and reduce and streamline the time and resources needed to meet the statutory and regulatory requirements for reducing regional haze in National Parks, wildlife refuges, and wilderness areas.  

EPA considered public comments on a 2016 draft document when developing the 2019 final guidance. 

On September 10, 2019, EPA hosted a webinar giving an overview of its Guidance on Regional Haze State Implementation Plans for the Second Implementation Period. The slides from the webinar are available below.

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