UNITED STATES ENVIRONMENTAL PROTECTION AGENCY W ASHINGTON, D
. C
. 20460

The Honorable Mary Fallin Governor of Oklahoma 2300 North Lincoln Boulevard, Room 212 Oklahoma City, Oklahoma 73105 Dear Governor Fallin: THE ADM I NISTRAT OR

I am writing to summar ize the U.S. Environmental Protection Agency's recent action to address fine particle pollution in you.r state. As required by the C lean 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 violat ions of the standard. On December 14 ,2012, the EPA strengthened the annual, health -based fine particle standard from 15.0 micrograms per cubic meter (11g/m 3) to 12.0 11g/m 3 • 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 diseas.e, nonfatal heart attacks, and increased hospital admis sions and doctor and emergency room visi ts for respiratory and cardiovascular disease. I appreciate the information you and your staffh ave shared with the EPA throughout this proces s to assess fine particle pollution levels in communities across your state and the impact of emission sources that could be contributing to unhealthy air. After considering your recommendations, reviewing the most recent certified fine particle air quality data for your state and evaluating factors to assess contribution to nearby levels of fine particle pollution , I have determined that no area within Oklahoma violates the 2012 standa rd or contributes to a nearby violation of the standard. As a result, the EPA is designating all of Oklahoma " uncla ssifiable/a ttairunent. " 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 27,20 15. 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 reduc e unhealthy levels of fine particle pollution. In addition, current and upcoming federal standard s 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.

I n ternet A dd r es s (URL) • http ://www
. e p a . gov Recycled/ Recyclable • P rin ted w i t h Vegetable O i l Bas ed I nks on 1 00% Poslconsumer. Process Chlori ne Free Recyc l ed Pape rTogether, we have made considerable progress to r educe fine particle pollution. Nationwide , monitored levels of fine particle pollution fell 34 percent since 2000 when we first began nationwide monitoring for particles of this size. I am confiden t this progress will accelerate as toget her we cont i nue to work towards our shared goal of clean air. For additional information about the se designations, please visit our website at: www.epa.gov / pmdesignations . I f you have questions or concerns, please contact me or your staff may contact Mark Rupp, Deputy Associate Administrator for Intergovernmental Relations , at rupp.mark@epa . gov or at (202) 564-7178 .