All National Ambient Air Quality Standards (NAAQS) undergo periodic review and may be revised to reflect the latest health, environmental and technological advances. When a new standard is promulgated or an existing standard is revised for particulate matter (PM), the first step in implementation is to determine which areas are, or are not, violating the NAAQS or are contributing to a violation of the NAAQS. During the “designation process,” states submit ambient air monitoring data and designation recommendations, which United States Environmental Protection Agency (U.S. EPA) reviews and considers before issuing final designations. All areas of Indiana are designated attainment for PM. Following are documents relating to U.S. EPA’s air quality designations in Indiana for the PM NAAQS.
2024 Primary Annual PM2.5 Standard
- Draft Exceptional Events Demonstration Addressing the 2024 Annual Primary Fine Particles (PM2.5) National Ambient Air Quality Standard (NAAQS) for the South Bend, Indiana Area (November 18, 2024) [PDF]
- Draft Exceptional Events Demonstration Addressing the 2024 Annual Primary Fine Particles (PM2.5) National Ambient Air Quality Standard (NAAQS) for the Terre Haute, Indiana Area (November 6, 2024) [PDF]
2012 Primary Annual PM2.5 Standard
- Documents – December 27, 2018 to December 12, 2013 [ZIP]:
- Federal Register Notice Concerning U.S. EPA Approval of Revised Designation for Clark, Floyd, Lake, and Porter Counties, Indiana from “Unclassifiable” to “Unclassifiable/ Attainment” (December 27, 2018)
- Indiana’s Request for the Redesignation of Clark, Floyd, Lake, and Porter Counties, Indiana from “Unclassifiable” to “Attainment/Unclassifiable” under the 2012 Annual Particulate Matter NAAQS (July 3, 2018)
- Federal Register Notice Concerning U.S. EPA’s Change to the Initial Air Quality Designation for the Louisville, Kentucky-Indiana Area from “Nonattainment” to “Unclassifiable” (April 7, 2015)
- Federal Register Notice Concerning U.S. EPA’s Air Quality Designations for the 2012 Primary Annual PM2.5 Standard (January 15, 2015)
- Updated Monitoring Data and Request for Reconsideration of Nonattainment Designations for Clark and Floyd Counties with Enclosure 1 (January 14, 2015)
- U.S. EPA Letter Concerning Final Designations for Indiana for the 2012 Primary Annual PM2.5 Standard (December 18, 2014)
- Indiana’s Response to U.S. EPA’s Preliminary Designations for the 2012 Primary Annual PM2.5 NAAQS (October 22, 2014)
- U.S. EPA Letter Concerning Preliminary Designations for the 2012 Primary Annual PM2.5 NAAQS with Enclosure (August 19, 2014)
- IDEM Map of U.S. EPA Preliminary Recommendations for Nonattainment Areas
- Technical Addendum to Provide Updated Monitoring Data for Indiana’s Initial Recommendations, Transmittal Letter and Enclosures 1-2 (May 12, 2014)
- Indiana’s Preliminary Recommendations for Designations under the 2012 Primary Annual PM2.5 Standard, Transmittal Letter and Enclosures 1-4 (December 12, 2013)
2006 24-Hour PM2.5 Standard
- Documents – November 13, 2009 to October 2, 2008 [ZIP]:
- Federal Register Notice Concerning U.S. EPA Air Quality Designations for 2006 24-Hour PM2.5 NAAQS Based on Updated 2006-2008 Monitoring Data (November 13, 2009)
- Indiana Letter and Enclosure Providing Updated 2006-2008 Monitoring Data for U.S. EPA Air Quality Designations (February 18, 2009)
- U.S. EPA Letter Concerning Final Designations Based on 2005-2007 Monitoring Data with Enclosure (December 22, 2008)
- IDEM Map of U.S. EPA’s Intended Nonattainment Areas Based on 2005-2007 Monitoring Data
- Response to U.S. EPA’s Intended Designations, Transmittal Letter and Attachments A-C (October 20, 2008)
- Attachment D
- Attachment E
- Indiana’s Comments and Request for Reconsideration of U.S. EPA’s Intended Designations, Letter and Attachments A-C (October 2, 2008)
- Attachment D
- Documents – August 18, 2008 to June 13, 2008 [ZIP]:
- U.S. EPA’s Letter Concerning Intended Modifications to Indiana’s Designation Recommendations (August 18, 2008)
- IDEM Map of U.S. EPA Preliminary Recommendations
- Letter Concerning the Revision of Appendix A for Exceptional Events Submitted with Indiana’s May 30, 2008 Designation Recommendations (June 13, 2008)
- Appendix A
- U.S. EPA’s Letter Concerning Intended Modifications to Indiana’s Designation Recommendations (August 18, 2008)
- Documents - May 30, 2008
- Part 1 [ZIP]:
- Indiana’s Designation Recommendations Based on 2005-2007 Data, Transmittal Letter and Enclosures 1-4
- Part 2 [ZIP]:
- Appendix A
- Part 3 [ZIP]:
- Appendices B-E
- Part 4 [ZIP]:
- Appendix F
- Part 5 [ZIP]:
- Appendix G
- Part 1 [ZIP]:
- Document – December 17, 2007
Previous PM Standards
U.S. EPA’s Green Book provides information concerning designations under previous standards:
IDEM’s Nonattainment Status for Indiana Counties page includes additional nonattainment history.