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News Releases

News Releases from Region 04

EPA Announces the Redesignation of the Hillsborough County and the Hillsborough-Polk Areas for the 2010 1-Hour Sulfur Dioxide (SO2) Standard

All areas of Florida now in attainment for sulfur dioxide

Contact Information: 
Dawn Harris-Young (
(404) 562-8421 (Direct), (404) 562-8400 (Main)

TAMPA, Fla. (March 5, 2020) – Today, the U.S. Environmental Protection Agency (EPA) announces that the Agency has taken final action to approve the state of Florida’s requests to redesignate both the Hillsborough County and the Hillsborough-Polk Areas from nonattainment to attainment for the 2010

1-Hour Sulfur Dioxide (SO2) standard.

With these redesignation actions, the entire state of Florida is in attainment for all of the National Ambient Air Quality Standards (NAAQS).  EPA has worked closely with the Florida Department of Environmental Protection (FDEP) to redesignate three areas from nonattainment to attainment for the SO2 standard – Nassau County, Hillsborough County, and Hillsborough-Polk.

“This milestone achievement represents years of hard work and dedication on behalf of FDEP as well as local businesses committed to improving the health and prosperity of Florida residents,” said EPA Administrator Andrew Wheeler. “We’re proud to assist areas like Hillsborough, Nassau and Polk Counties achieve not only their air quality goals, but also attract and retain much-needed jobs.”

“Working in partnership with the state, we have achieved significant improvements in air quality in the state of Florida,” said EPA Region 4 Administrator Mary S. Walker. “Achieving air quality attainment is a tremendous step in providing a healthy environment for Floridians.”

“Achieving our environmental protection goals takes collaboration,” said Florida Department of Environmental Protection Secretary Noah Valenstein. “The work that DEP, along with EPA, has done with industry members in Hillsborough, Nassau and Polk counties has resulted in improved air quality, better protecting public health and the quality of life of our residents and visitors. I am proud of our efforts that have led Florida to being the populous state in the United States to meet all national ambient air quality standards.”

For over 10 years, FDEP has worked collaboratively with EPA and other stakeholders to develop air quality strategies for achieving and maintaining compliance with the 2010 1-hour SO2 standard across the state.

The largest sources of SO2 emissions are from fossil fuel combustion at power plants and other industrial facilities.  The Hillsborough County Area includes two primary sources of SO2 - Mosaic Fertilizer, LLC Riverview facility, and Tampa Electric Company Big Bend power plant.  The Hillsborough-Polk Area also includes two primary sources of SO2 – Mosaic Fertilizer, LLC New Wales facility and Mosaic Fertilizer, LLC Bartow facility.  Reduction of SO2 emissions at these sources have helped bring the Hillsborough County and Hillsborough-Polk Areas into attainment.

For more information on the Hillsborough County Area and Hillsborough-Polk Area final 2010 1-Hour SO2 redesignations, visit docket numbers EPA-R04-OAR-2018-0552 and EPA-R04-OAR-2018-0510, respectively, at

How EPA works with states to reach attainment for SO2 emissions