UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C. 20460

The Honorable Mike Pence Governor ofIndiana Statehouse, Room 206 Indianapolis, Indiana 46204-2797 Dear Governor Pence: 

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THE ADMINISTRATOR

I am writing to summar ize the U.S. Environmental Protection Agency 's rec ent 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 emis sions that contribute to vio lations of the standard. On December 14 , 2012, the EPA strengthened the annual , health-based fine partic le standard from 15.0 micrograms per cubic meter ()lg/m 3) to 12.0

**~Lg /m** 

**.** Thousands of scientific s tudies have linked expo s ure to these tiny particle s-approx imately l/30t h the size of a human hair

- with se rious human health prob le ms including premature death in people with heart and lung disease , no nfatal heart attacks, and increased hospital admissions and doctor and emergency room visits for resp irato ry and cardiovascu lar 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 th e impact of emission sources that co uld be contributing to unhealthy air. After consider ing your recommendations, reviewing the most recent certified fine particle air qua li ty data for your state and evaluating factors to assess contribution to nearby leve ls of fine particl e pollution, I have determined that most areas in your state meet the 2012 annual fine particle standard. As a result, the EPA is des ignating the maj ority of the s tate " unclassifiable/attainment. " Also, some areas in your s tat e do not meet the 2012 annual fine particle standard or contribute to a nearby violation of the s tandard. The EPA is designating those areas " nonattainment. " Nonattainment areas will be required to take action to reduc e fine particle pollution and meet the standard no later than 2021
. As required by the C lean Air Act, those actions may include stricter controls on industri al facilities and additional planning requirements for transportat ion-related sources.

Internet Address (URL) • http : //www
. epa .gov Recycled/Recyclable • Printed with Vegetable O i l Based I nks on tOO% Postconsumer, Process Chlorine Free Recycled PaperAs we have been discussing with your staff, the EPA identified data quality issues earlier this year that invalidated fine particle pollution monitoring data for the state of Illinois. Because of these data issues, the EPA cannot determine at this time whether the Illinois portion of the Chicago , IL- IN area is meeting the standard. As a result, even though the monitors in the Indiana portion of the Chicago, IL-IN area are showing attainment, the EPA does not have sufficient information to determine whether these Indiana counties do or do not contribute to a nearby violation in Illinois. Along with the state of Illinois, EPA is designating the Indiana counties in that area " 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 in the Chicago, IL- IN area once sufficient complete air monitoring data are available. The enclosed table lists the areas and counties in Indiana that the EPA is designating nonattainment and unclassifiable. Because air quality monitoring for 2014 is nearly complete, if a state or tribe requests it, the EPA will evaluate the status of an area based on its annual fine particle monitoring data for 2012-2014. If you would like the EPA to re-evaluate any areas within your state , please submit to the EPA, complete, quality-assured and certified air quality data for 2014 by February 27,2015. 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 fi n e particle pollution. ln addition, current and upcoming federal standards and safeguards, including pollution r e duction 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. 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 si z e. 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: vvww.epa.gov/pmdcs i gnat i ons .

If you have questions or concerns, please contact me or your staff may contact Mark Rupp, Deputy Associate Administrator for Intergovernmental Relations, at ru pp. mark(a),e p a. g ov or at (202) 564-7178. · J r el y ,**~** Enclosure

### Enclosure- Initial Area Designations for the 2012 Annual Fine Particle Standard, Indiana

State Area Name 2014 EPA Designated Nonattainment Counties IN Loui svill e, KY-IN Clark, IN Floyd , IN 

### Statefferritory Area Name 2014 EPA Designated Unclassifiable Counties IN Chicago, IL-IN Lake, IN Porter, IN