UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

The Honorable Pat Quinn 

Governor of Illinois 

State Capitol 

207 Statehouse 

Springfield, Illinois 6060 I 

Dear Governor Quinn: 

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THE ADMINISTRATOR 

I am writing to summarize the U.S. Environmental Protection Agency's recent action to address fine 

particle pollution in your state. As required by the Clean Air Act, the EPA has determined which areas 

are meeting the national ambient air quality standards for fine particle pollution and which areas must 

take steps to reduce emissions that contribute to violations of the standard. 

On December 14,2012, the EPA strengthened the annual, health-based fine particle standard from 15.0 

micrograms per cubic meter (~-tg ) to 12.0 ~-tg/m . Thousands of scientific studies have linked exposure 

to these tiny particles-approximately l/30th the size of a human hair-with serious human health 

problems including premature death in people with heart and lung disease, nonfatal heart attacks, and 

increased hospital admissions and doctor and emergency room visits for respiratory and cardiovascular 

disease. 

I appreciate the information you and your staff have shared with the EPA throughout this process to 

assess fine particle pollution levels in communities across your state and the impact of emission sources 

that could be contributing to unhealthy air. The EPA identified data quality issues earlier this year that 

invalidated fine particle pollution monitoring data for your state. As a result, the EPA cannot determine 

based on available information whether areas in Illinois are meeting the 20 I 2 standard or contribute to a 

nearby violation, and the EPA is designating the state "unclassifiable." The EPA will work closely with 

Illinois to ensure that identified problems with air quality monitoring data are corrected. The agency 

intends to reassess levels of fine particle pollution throughout Illinois once sufficient complete air 

monitoring data are available. 

The EPA shares responsibility with the states and tribes for managing particle pollution levels. Efforts 

by states and tribes to attain the 1997 and 2006 fine particle pollution standards are already working to 

reduce unhealthy levels of fine particle pollution. In addition, current and upcoming federal standards 

and safeguards, including pollution reduction rules for power plants, vehicles and fuels will assure 

steady reductions of fine particle pollution and will protect public health in communities across the 

country. 

Internet Address (URL) • http://www.epa gov 

Recycled/Recyclable • Pnnted With Vegetable Oil Based Inks on 100% Postconsumer. Process Chlorine Free Recycled Paper 
Together, we have made considerable progress to reduce fine particle pollution. Nationwide, monitored 

levels of fine particle pollution have fallen 34 percent since 2000 when we first began nationwide 

monitoring for particles of this size. I am confident this progress will continue as we work together 

towards our shared goal of clean air. For additional information about these designations, please visit 

our website at: """'-v..epa.gov/pmdesignations. 

Sincerely, 

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