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Particulate Matter (PM) Pollution

PM2.5 Precursor Demonstration Guidance

This guidance is designed to assist air agencies who may wish to submit PM2.5 precursor demonstrations as permitted by the PM2.5 SIP Requirements Rule. The draft PM2.5 Precursor Demonstration Guidance was released on November 17, 2016 for consideration, review, and comment by state, local and tribal air agencies, as well as the public.  The comment period ended March 31, 2017. The EPA is currently considering all of the comments that were received and will make revisions to the draft guidance accordingly. Until such time as the release of the revised PM2.5 Precursor Demonstration Guidance, anyone seeking to use this draft guidance for regulatory purposes is encouraged to engage with their respective EPA Regional Office as early as possible.

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