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News Releases from Region 04

EPA Approves Redesignation of the Nassau County 2010 1-Hour Sulfur Dioxide (SO2) Standard

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

ATLANTA (April 26, 2019) – Today, the U.S. Environmental Protection Agency (EPA) announced that it is taking final action to approve the state of Florida’s request to redesignate the Nassau County Area from nonattainment to attainment for the 2010 1-Hour Sulfur Dioxide (SO2) standard.

“Working in partnership with the state, we were able to achieve significant improvements in air quality in the Nassau County area,” said EPA Acting Region 4 Administrator Mary S. Walker. “Meeting the national sulfur dioxide standard is a critical step in providing a healthy environment for Nassau County citizens.”

For almost 10 years, the Florida Department of Environmental Protection (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.

“Collaboration is a vital component of environmental protection,” said Florida Department of Environmental Protection Secretary Noah Valenstein. “In this case, this effort successfully generated a plan that has resulted in substantial emission reductions and greatly improved air quality in Nassau County and will ensure this continues into the future.”

The largest sources of SO2 emissions are from fossil fuel combustion at power plants and other industrial facilities. The Nassau County Area includes two primary sources of SO2.  The Rayonier Performance Fibers, LLC Fernandina Beach Sulfite Pulp Mill is located within the Area, while WestRock CP, LLC Fernandina Beach Mill is located adjacent to the Area and is the largest source of SO2 immediately outside of the Nassau County Area. Reduction of SO2 emissions at both sources have helped bring the Nassau County Area into attainment.

Since SO2 is used as the indicator for the larger group of gaseous sulfur oxides, also known as SOx, EPA’s national ambient air quality standards for SO2 are designed to protect against exposure to the entire group of SOx .  Control measures that reduce SO2, the sulfur oxide of greatest concern, can be expected to reduce people’s exposures to all gaseous SOx.

Short-term exposures to SO2 can harm the human respiratory system and make breathing difficult.  People with asthma, particularly children, are sensitive to these effects of SO2.  Control measures that reduce SO2 emissions can also help reduce the formation of small particles that can contribute to fine particulate matter pollution.  Fine particulates may penetrate deeply into the lungs and in sufficient quantity can contribute to health problems.

For more information on the Nassau County Area final 2010 1-Hour Sulfur Dioxide (SO2) redesignation, visit docket number EPA-R04-OAR-2018-0523 at