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Support Center for Regulatory Atmospheric Modeling (SCRAM)

11th Conference on Air Quality Modeling

Proposed Rulemaking Information:

On July 14, 2015, the Administrator signed a proposal to revise the Guideline on Air Quality Models. The Guideline provides U.S. Environmental Protection Agency (EPA) recommended models and other techniques, as well as guidance for their use, for predicting ambient concentrations of air pollutants. EPA’s proposed changes would, enhance the formulation and application of the agency’s AERMOD dispersion model, prescribe modeling techniques for secondarily formed fine particle and ozone pollution for single sources and makes various editorial improvements.

Conference and Public Hearing Information:

On July 14, 2015, the U.S. Environmental Protection Agency (EPA) announced the Eleventh Conference on Air Quality Modeling and invited the public to participate in the conference. The modeling conference, mandated by Section 320 of the Clean Air Act, was held on the EPA RTP Campus from August 12th through 13th, 2015. The conference was focused on the proposed revisions to the Guideline on Air Quality Models (CFR Title 40, Part 51, Appendix W) and served as the public hearing for those proposed revisions.

The Eleventh Conference on Air Quality Modeling began with a morning of EPA presentations providing an overview of the various proposed revisions to the Guideline. The remainder of the conference was dedicated to public presentations that provided comment to the EPA on the proposed rulemaking.

Disclaimer: The material provided below were presented during the proceedings of the Eleventh Conference on Air Quality Modeling. The information contained in some of these presentations may not reflect U.S. EPA policy and should not be considered as an official endorsement of the Agency. The presentations given on Wednesday, August 12 and Thursday, August 13, 2015 during the Public Presentation and Comments Session were public comments being presented to the Agency for consideration.

Transcripts and Audio Recordings:

Conference Review Material:

Please direct any additional questions concerning the Eleventh Conference on Air Quality Modeling to Mr. George Bridgers, email: