The Honorable Pat Quinn 

207 Statehouse 

Springfield, lllinois 62706 

Dear Governor Quinn: 

Thank you for your recommendations dated December 12, 201 3, of air quality designations for 

the 2012 revised primary annual fine pmiicle (PM2.s) National Ambient Air Quality Standard 

(NAAQS) throughout Illinois. I appreciate the information Illinois shared with the U.S. 

Environmental Protection Agency as we move forward to improve PM2 s air quality. This letter 

is to notify you ofEPA's preliminary response to Illinois' recommendations and to inform you 

of our approach for completing the initial area designations for the 2012 revised primary annual 

PM2s standard. 

On December 14,2012, EPA promulgated a revised primary annual PM2.s NAAQS (78 FR 3086, 

January 15, 2013). In that action, EPA revised the primary annual PM2.s standard, strengthening 

it from 15.0 micrograms per cubic meter (11g/m3) to 12.0 11g/m3; retained the existing 24-hour 

PM2s standard at 35 11g/m3; retained the existing 24-hour PMw (coarse particle) standard at 150 

11g/m3 ; and retained the current suite of secondary PM standards. EPA revised the primary 

armual PM2.s standard based on an integrated assessment of an extensive body of new scientific 

evidence, which substantially strengthens our body of knowledge regarding PM2.s-related health 

effects. The revised primary annual PM2.s standard will provide increased protection for 

children, older adults, persons with pre-existing heart and lung disease, and other at-risk 

populations against an array ofPM2.s-related adverse health effects, including premature 

mortality, increased hospital admissions and emergency department visits, and development and 

exacerbation of chronic respiratory disease. 

History shows us that better health and cleaner air go hand-in-hand with economic growth. 

Working closely with the states and tribes, EPA is implementing the standards using a 

commonsense approach that improves air quality and minimizes the burden on state, local, and 

tribal governments. As part of this process, EPA is working with the states and tribes to identify 

areas in the country that meet the standards and those that need to take steps to reduce PM2.s air 

pollution. Within one year of promulgation of a new or revised air quality standard, the Clean 

Air Act requires the Governor of each state to submit to EPA a list of all areas in the state, with a 

designation recommendation for each area. As a first step in implementing the 2012 annual 

PM2.s standard, Governors were to submit their designation recommendations, including 

appropriate area boundaries, by December 13,2013. 

Recycled/Recyclable • Printed with Vegetable Oil Based Inks on 100% Recycled Paper (100% Post-Consumer) 
cannot determine based on available information whether the area is meeting the NAAQS or 

where EPA has not determined that the area contributes to a nearby violation. At this time, EPA 

is proceeding with initial area designations using quality-assured, certified air quality monitoring 

data from 2011 to 2013. 

EPA has reviewed the annual PM2.s designation recommendations submitted by Illinois on 

December 12, 2013, and other relevant technical information, including 2011-20 !3 air quality 

data. However, a recent EPA-conducted technical systems audit of Illinois' monitoring program, 

in particular our audit of the procedures that the Cook County Department of Environmental 

Control has used in weighing PM2.s samples collected across the state, revealed that many if not 

all of the recent PM2.s monitoring data for the entire State of Illinois needed to be considered 

invalid. As a result, EPA does not have sufficient valid data to determine whether any portion of 

Illinois is meeting or not meeting the NAAQS or whether counties nearby to those counties with 

incomplete monitoring data contribute to a nearby violation. Accordingly, EPA intends to 

modify Illinois' recommended area designation and designate the State of Illinois as 

unclassifiable. A Technical Support Document, which provides additional detail regarding the 

status of data for Illinois and the rationale to support EPA's unclassifiable designation, is 

enclosed and is also available on EPA's website at 

http://v.ww.cpa. gov /pmdesignations/20 12standqrds/statc. htm. If Illinois has additional 

information for EPA to consider, please submit it to us by October 29,2014. 

EPA will make its proposed designation decisions and supporting documentation available to the 

general public for review and comment. We will be announcing a 30-day public comment 

period shortly in the Federal Register. After considering the additional information we receive, 

EPA plans to promulgate final mmual PM2.s designations in December of2014. 

EPA is committed to working with the states and tribes to share the responsibility of reducing 

PM2.s air pollution. Current and upcoming federal standards and safeguards- including 

pollution reduction rules for power plants, vehicles, and fuels- will ensure steady progress to 

reduce PM25-forming pollution and will protect public health in communities across the country. 

We look forward to a continued dialogue with you and your staff as we work together to 
Susan Hedman 

Regional Administrator 

Enclosures 

cc: Lisa Bonnett 

Director, Illinois Environmental Protection Agency 

Julie Armitage 

Chief, Bureau of Air 

Illinois Environmental Protection Agency