An official website of the United States government.

We've made some changes to EPA.gov. If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Clean Air Markets

March 2018 Memo and Supplemental Information Regarding Interstate Transport SIPs for the 2015 Ozone NAAQS

On March 27, 2018, EPA provided projected air quality modeling results for ozone in 2023 including projected ozone concentrations at potential nonattainment and maintenance sites for the 2015 ozone NAAQS and projected upwind state contribution data.  States can use these data to develop their implementation plans to assure that emissions within their jurisdictions do not contribute significantly to nonattainment or interfere with maintenance of the 2015 ozone standards in other states.  EPA also provided, as Attachment A to this memorandum, a preliminary list of potential flexibilities in analytical approaches for developing a good neighbor SIP that may warrant further discussion between the EPA and states.

During stakeholder calls in April 2018, the EPA asked stakeholders to provide feedback on the March 27, 2018 memo. The EPA received written comments, which are provided below.

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.