Air Plan Approval; KY; Fine Particulate Matter and Ozone NAAQS Revisions

The Environmental Protection Agency (EPA) is proposing to approve portions of State Implementation Plan (SIP) revisions submitted by the Commonwealth of Kentucky, through the Kentucky Division for Air Quality, on December 21, 2016 and August 29, 2017, on behalf of the Louisville Metro Air Pollution Control District (District). EPA is proposing to approve the portions of the submittals that modify the District's Ambient Air Quality Standards regulation, as incorporated into the SIP. The revisions to the SIP that EPA is proposing to approve pertain to changes to the District's air quality standards for fine particulate matter (PM2.5) and ozone to reflect the 2012 PM2.5 and 2015 ozone national ambient air quality standards (NAAQS). EPA is proposing to approve these portions of the SIP revisions because the Commonwealth has demonstrated that they are consistent with the Clean Air Act (CAA or Act). EPA will act on the other portions of the December 21, 2016, and August 29, 2017, submittals in a separate action.