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EPA Approves Revisions to Kentucky Regional Haze Plan

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EPA Press Office (

Louisville, Ky. (April 12, 2019) – U.S. Environmental Protection Agency (EPA) Administrator Andrew Wheeler has approved revisions to the Kentucky Regional Haze State Implementation Plan (SIP) for sulfur dioxide and nitrogen oxides emissions at electric generating units within the commonwealth. Administrator Wheeler’s approval removes the one-size-fits-all Federal Implementation Plan (FIP) for Kentucky regional haze dating back to 2012 and fully approves Kentucky’s clean air plan for regional haze.

“EPA is removing burdensome, top-down federal requirements and approving the commonwealth’s own plan for clean air and visibility,” said EPA Administrator Andrew Wheeler. “This action reflects President Trump’s commitment to reduce regulatory burdens imposed on states and work cooperatively with them to achieve environmental progress.”

“EPA is pleased to announce the approval of Kentucky’s regional haze plan,” said EPA Acting Region 4 Administrator Mary S. Walker. “This action returns the authority to implement these clean air provisions to the commonwealth.”

“The Kentucky Department for Environmental Protection (KDEP) appreciates EPA’s recent approval of the Kentucky Regional Haze State Implementation Plan,” noted KDEP Commissioner Anthony Hatton.  “In the last 10 years, emissions of sulfur dioxide and nitrogen oxides from Kentucky electric generating units have decreased by 78% and 40%, respectively.” 

The approved plan reduces regional haze in Kentucky’s Mammoth Cave National Park and “class I areas” in nearby states affected by air emissions from the commonwealth. Kentucky’s revised plan is an example of the positive environmental outcomes that EPA is achieving across the country from a cooperative federalism approach.

Under the Clean Air Act, states are required to develop SIPs that ensure reasonable progress toward the national goal of reducing visibility impairment in “class I areas” like national parks and wilderness areas by reducing harmful emissions of certain air pollutants such as sulfur dioxide, nitrogen oxides, and fine particulate matter. FIPs have been imposed when EPA disapproves or only partially approves a SIP or when states do not submit SIPs.

EPA is working to convert many previously issued FIPs into SIPs. This includes action on regional haze FIPs for more than a dozen states since early 2017.

In 2018, EPA Acting Administrator Wheeler issued a Regional Haze Reform Roadmap, setting a path that puts states in charge and reduces state planning burdens. The approval of Kentucky’s Regional Haze SIP is another example of successful federal/state collaboration as EPA supports states to enable efficient, timely and effective implementation of the Regional Haze program.