UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION IX 75 Hawthorne Street San Francisco, CA 94105-3901

OFFICE OFTHE REGIONAL ADMINISTRATOR 

## DEC 0 9 2011

The Honorable Brian Sandoval The State ofNevada 101 North Carson Street Carson City, Nevada 89701
Dear Governor Sandoval: Thank you for your recommendations dated March 10,2009 and November 18, 2011 on air quality designations for the revised 2008 National AmbientAir Quality Standards for ozonethroughout Nevada. I appreciate the information Nevada shared with the U.S. Environmental Protection Agency as we move forward to improve ozone air quality. Thepurpose ofthis letter is to notify you ofthe U.S. Environmental Protection Agency'spreliminary decision to designate Nevada as unclassifiable/attainment for the revised 2008 ozone NAAQS, according to your recommendations, and to inform you ofour approach for completingthe designations for the revised ozone NAAQS.
On March 12,2008,the EPArevised its NAAQS for ground-level ozone to provide increased protection ofpublic health and the environment. The EPA lowered the primary 8-hour ozone standard from 0.08 parts per million (ppm) to 0.075 ppm to protect against health effects associated with ozone exposure, including a range ofserious respiratory illnesses and increasedpremature death from heart or lung disease. The EPA revised the secondary 8-hour ozone standard, making it identical to the primary standard, to protect against welfare effects, including impacts on sensitive vegetation and forested ecosystems. History shows us thatbetterhealth and cleaner air go hand-in-hand with economic growth. Working closelywith the states and tribes, the EPA is implementingthe standards using a common sense approach that improves air quality and minimizes the burden on state and local governments. As part ofthis routine process, EPA is working with the states to identify areas in the countrythat meetthe standards and those that need to take steps to reduce ozone pollution. Within one year after a new or revised air quality standard is established, the Clean AirActrequires the Governor ofeach state to submitto the EPA a list ofall areas in the state, with recommendations for whether each area meets the standard.
As a first step in implementingthe 2008 ozone standards, the EPA asked states to submittheir designation recommendations, including appropriate area boundaries, byMarch 12,2009. In 

### September 2009, the EPA announced it was reconsidering the 2008 ozone standards. The EPA later took steps to delaythe designation process for the 2008 ozone standards pending outcome ofthe reconsideration. However, in September 2011, the Office ofManagement and Budget returned to EPAthe draft final rule addressing the reconsideration ofthe 2008 standards. On September 22, 2011, the EPA restarted the implementation effort by issuing a memorandum to clarify for state and local agencies the

Printed on RecycledPaperstatus ofthe 2008 ozone standards and to outline plans for moving forward to implement them. 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 by the most current, certified air quality data from 2008­ 2010. While the EPA did not request that states submitupdated designation recommendations, the EPA provided the opportunity for states to do so. Thankyou for the November 18, 2011 updated designation recommendation from Nevadabased on the assessment ofpreliminary2009-2011 air qualitydata.
As required bythe 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 meeting the ozone standards orthere are no monitoring data for the area, and the EPA has not made a determination that the area is contributingto a violation in a nearby area. AfterconsideringNevada'sNovember 18,2011 ozone designation recommendation, which was based on preliminary2009-2011 air quality data, as well as otherrelevant technical information, the EPA intends to designate the entire state ofNevada as unclassifiable/attainment. Inorder for the EPA to consider2009-2011 air quality data in the final designation decisions for this area, Nevada must submit certified, quality-assured 2009-2011 air quality monitoring data for the area to the EPA byFebruary 29,2012.
The EPA will also make its preliminary designation decisions and supporting documentation available to the general public for review and comment. We will beannouncing a 30-daypublic commentperiod shortly in the 

### FederalRegister. After considering additional information we receive, the EPA plans to promulgate final ozone designations in the spring of2012.
The EPA is committed to working with the states and tribes to share the responsibility ofreducing ozone airpollution. Current and upcoming federal standards and safeguards, including pollution reduction rules for powerplants, vehicles and fuels, will assure steadyprogress to reduce ozoneforming pollution and will protectpublic health in communities across the country. We lookforward to a continued dialogue with you and your staffas we work together to implementthe 2008 ozone standards. Should you have any questions, please do not hesitate to contact me orAmyZimpfer, Associate Director, AirDivision, ofmy staffat 415-947-4146 or zimpfer.amy@epa.gov. Sincerely, 

# h

Jared Blumenfeld

cc: Colleen Cripps, Administrator, NevadaDepartmentofEnvironmental Protection Mike Elges, DeputyAdministrator, Nevada Department ofEnvironmental Protection Rob Bamford, Bureau Chief, Bureau ofAir QualityPlanning, Nevada Department of Environmental Protection Gina McCarthy, Assistant Administrator for Air and Radiation Stephen D. Page, Director, Office ofAir QualityPlanning and Standards