UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION6 1445 ROSS AVENUE, SUITE 1200 DALLASTX 75202-2733 

### DEC 9 - 2011
The Honorable Mary Fallin Governor ofOklahoma 2300 North Lincoln Boulevard, Suite 212 Oklahoma City, Oklahoma 73105
Dear GovernorFallin:
Thank you for yourrecommendations dated October 11, 2011, on air quality designations for the revised 2008 National AmbientAir Quality Standards for ozone throughout Oklahoma. I appreciate the information Oklahoma shared with the U.S. Environmental Protection Agency (EPA) as we move forward to improve ozone air quality. This letteris to notify you ofthe EPA's preliminary response to Oklahoma's recommendations and to inform you ofour approach for completing the designations for the revised ozone standards.
On March 12, 2008, the EPA revised its national ambient air quality standards for ground-level ozone to provide increased protection ofpublic health and the environment. The EPA lowered the primary 8-hourozone standard from 0.08 parts permillion (ppm) to 0.075 ppm to protect against health effects associated with ozone exposure, including a range ofserious respiratory illnesses and increased premature death from heart orlung disease. The EPA revised the secondary 8-hourozone standard, making it identical to the primary standard, to protect against welfare effects, including impacts on sensitive vegetation and forested ecosystems. History shows us that betterhealth and cleaner air go hand-in-hand with economic growth. Working closely with the states and tribes, the EPA is implementing the standards using a common sense approach that improves air quality and minimizes the burden on state and local governments. As part ofthis routine process, the EPA is working with the states to identify areas in the country that meetthe standards and those that need to take steps to reduce ozone pollution. Within one year after anew orrevised air quality standard is established, the Clean Air Act requires the governor of each state to submit to the EPA a list ofall areas in the state, with recommendations for whether each area meets the standard. As a first step in implementing the 2008 ozone standards, the EPA asked states to submit their designation recommendations, including appropriate areaboundaries, by March 12,2009. In September2009, the EPA announced it was reconsidering the 2008 ozone standards. The EPA latertook steps to delaythe designationprocess for the 2008 ozone standards pending outcome ofthe reconsideration. However, in September2011, the Office ofManagement and Budget returned to the EPA the draftfinal rule addressing the reconsideration ofthe 2008 ozone standards. On September22, 2011, the EPA restarted the implementation effortbyissuing a memorandum to clarifyfor state and local agencies the status ofthe 2008 ozone standards and to outline plans for moving forward to implementthem. The EPA indicated that it would proceed with initial area designations for the 2008 standards, and planned to use the recommendations states made in 2009 as updated bythe most current, certified air quality data from 2008-2010. While the EPA did notrequest that states submitupdated designation recommendations, the EPA providedthe opportunity for states to do so. Thank you for the October 11, 2011, updated designation recommendation from Oklahoma based on the assessment of2008-2010 air quality data.

Internet Address (URL) • http://www.epa.gov/region6 Recycled/Recyclable. Printed with Vegetable Oil Based Inks on 100% Recycled Paper, Process Chlorine FreeAs required by the Clean AirAct, the EPA will designate an area as nonattainment ifit is violating the 2008 ozone standards orcontributingto a violation ofthe standards in a nearby area. Consistent with designations for previous ozone standards, the EPA intends to designate an area as unclassifiable/attainment ifthere are certified, quality-assured air quality monitoring data showing the area is meetingthe ozone standards orthere are no monitoring data for the area, and the EPA has not made adetermination thatthe area is contributing to aviolation in anearby area. Afterconsidering the October20II ozone designation recommendations from Oklahoma and other relevant technical information, including 2008-20I0 airquality data, the EPA intends to designate the entire state ofOklahoma as unclassifiable/attainment.
IfOklahoma has additional information that you would like the EPA to consider, please submit it to us by February29,2012. The EPA will also make its preliminary designation decisions and supporting documentation available to the general public forreview and comment. We will be announcing a 30-daypublic comment period shortly in the FederalRegister. After considering additional information we receive, the EPA plans to promulgate final ozone designations in spring of2012.
The EPA is committed to working with the states and tribes to share the responsibilityofreducing ozone airpollution. Current and upcoming federal standards and safeguards, including pollution reduction rules forpowerplants, vehicles and fuels, will assure steady progress to reduce ozone-forming pollution and will protect public health in communities across the country. We look forward to a continued dialogue with you and your staffas we work together to implement the 2008 ozone standards. Should you have anyquestions, please do not hesitate to contactme at (214) 665-2100, orhave your staffcontact Mr. Guy Donaldson ofmy staffat (214) 665-7242.
Since

Enclosure

cc: Mr. Gary Scherrer, Oklahoma Secretary ofthe Environment
Mr. Steven Thompson, Executive Director, OklahomaDepartment ofEnvironmental Quality
Mr. Eddie Terrill, DirectorofAir Quality, OklahomaDepartment ofEnvironmental Quality