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

OFFICE OF THE REGIONAL ADMINISTRATOR 

### OCT 1 4 2009
The Honorable Jan Brewer Governor ofArizona 1700 West Washington Phoenix, AZ 85007 Dear Governor Brewer: I am writing in follow-up to Administrator Lisa Jackson's October 8 letter notifying you that the U.S. Environmental Protection Agency (EPA) has determined that changes are necessary to air quality designations within your state. As explained in more detail below, these changes include promulgation ofan initial designation ofnonattainment for the 2006 24-hour national ambient air quality standard (NAAQS) for fine particles (PM25), a revised designation ofnonattainment for the 1997 annual PM2
.5NAAQS, and a revised designation ofnonattainment for the 1987 24-hour PM IO NAAQS. These changes are necessary based upon violations ofall three standards in Pinal County, reflected in the most recently available air quality monitoring data for this area for 2006-2008. Designation for the 2006 24-hour PM2
.5NAAQS Your state submitted its initial list ofrecommendations for designations to EPA by letter from Janet Napolitano, Governor, dated December 19,2007. Last year, EPA notified you ofits agreement with those recommendations by letter from Wayne Nastri, Regional Administrator, dated August 8, 2008. EPA had intended to finalize the designation decisions in December of2008. Due to the change ofAdministration, however, EPA did not complete the process at that time. Therefore, at the request ofthe new Administration, EPA has reviewed the status ofareas for the 2006 24-hour PM2
.5NAAQS in order to assure that the final decisions reflect current policy and the most up­ to-date air quality monitoring data. In particular, this review has allowed consideration of2006­ 2008 data for all areas. The new data indicate that an additional area in Arizona, Pinal County, now appears to be violating the 2006 24-hour PM2
.5NAAQS leading EPA to believe that further modifications to your state's initial recommendations maybe necessary. EPA is therefore deferring the designation for Pinal County for the 2006 24-hour PM2.5 NAAQS so that EPA can collect and evaluate additional information before promulgating a designation. Consistent with the approach used to assess other potential nonattainment areas, EPA also intends to evaluate relevant technical data for the ring ofcounties immediately surrounding Pinal County to determine whether any ofthese nearby counties contribute to the violation. EPA

Pn"nted on Recycled Paperis therefore deferring the designations for these counties l for the 2006 24-hour PM2

.5NAAQS so that EPA can collect additional information sufficient to assess these areas before promulgating designations. Werecognize that these are large geographical areas, and we recognize that the counties surrounding Pinal County are currently attainingthe 2006 24-hour PM2.5 NAAQS. Looking at the counties surrounding Pinal County is only a startingpoint for the**evaluation~** it should not be assumed that the final designated nonattainment area will include these counties. Consideration ofthe relatively long distances across which PM2 .5 and PM2.5 precursors can be transported shouldbebalanced with a key purpose ofdesignations, which is to identify those nearby contributing areas that should be included within a designated nonattainment area to ensure the development ofan appropriate State Implementation Plan for the area. This is explained further inthe Federal Register notice for final 24-hour PM2
.5designations, at www.epa.gov/pmdesignations/2006standards/regs.htm#3. Factors that shouldbe considered as the basis for nonattainment area boundaries are described in a guidance memorandum entitled "AreaDesignations for the Revised 24-Hour Fine Particle National Ambient Air Quality Standard" from Robert J. Meyers, dated June 8, 2007 (enclosed). When EPA's evaluation is complete, we will notify you ofourintended designation and boundary for this area. Following this notification, which we will provide at least 120 days prior to promulgating a final designation, you will have the opportunity to comment on EPA's intended designation and to provide additional information to inform the final decision. Designation for the 1997 annual PM2 .5 NAAQS On January 5, 2005, EPA designated Pinal County, and surrounding areas, as "unclassifiable/attainment" for the 1997 annual PM2 .5NAAQS because this area was then meeting the standard. Unfortunately, the mostrecent air quality monitoring data for PM2.5, for the period from 2006-2008, indicate that Pinal County is now violating the 1997 annual PM2 .5 NAAQS. As a result ofthis violation, EPA is initiating the process under Clean Air Act section 107(d)(3) to redesignate Pinal County, along with any nearby areas that maybe contributing to the violations in Pinal County, as "nonattainment" for the 1997 annual PM2.5 NAAQS. As a first step in this process, EPA is requesting that you provide your recommendations for the redesignation ofPinal County, and any nearby areas that maybe contributingto violations in Pinal County, within 120 days ofthe receipt ofthis letter. EPA recommends that you assess the geographic boundaries for this area using the guidance for nonattainment area boundaries that EPA previously provided for designations for the 1997 PM2 .5NAAQS. EPA provided this guidance in a Memorandum entitled "Designations for the Fine Particle National Ambient Air Quality Standards," from Jeffrey R. Holmstead, dated April 1,2003 (enclosed).
EPA also provided additional guidance on defining areaboundaries for PM25 designations in a memo from Lydia N. Wegman, dated February 12,2004 (enclosed). EPA believes that Pinal County and those nearby areas that maybecontributing to the violations are

I The additional counties for which EPA will defer designation are Cochise County, Gila County, Graham County, La Paz County, Maricopa County, Pima County, Yavapai County, and Yuma County. 2an appropriate startingpoint for the evaluation for this NAAQS and will evaluate your recommendation and the data in accordance with the previously issued guidance. Designation for the 1987 24-hour PM 10NAAQS Themostrecent air quality monitoring data for PMIO, for the period 2006-2008,indicate that Pinal Countyis now violating the 24-hour PMIO NAAQS. As a result ofthis violation, EPA is initiating the process to redesignate Pinal County, and any nearby areas that maybe contributing to the violations in Pinal County, as "nonattainment" for the 24-hour PMIO NAAQS. EPA is therefore requesting that you also provide your recommendations for the redesignation of Pinal County, and any nearby areas that may be contributing to violations in Pinal County, for this NAAQS within 120 days ofthe receipt ofthis letter. EPA recommends that you assess the geographic boundary for the 24-hour PMIO NAAQS in light ofthe different nature ofPM 10. Theboundary for this NAAQS mayormay not be comparable to those that are appropriate for the different particles addressed by the 2006 24-hour PM2.5 NAAQS and the 1997 annual PM2
.5NAAQS. We look forward to continuing to work with you and your staffto develop area designations. EPA will evaluate yourrecommendations and will work with your staffto assure that the final designations and boundaries for each oftheNAAQS are appropriate, based on the relevant facts and circumstances. Afterpromulgation ofthe new designations for this area for these NAAQS, EPA will likewise work with your staffto develop appropriate State Implementation Plans to assure the publichealth protections intendedbythe standards. Ifyou have any questions, please do not hesitate to contact me. Your air quality staffmay wish to contact Deborah Jordan, Air Division Director at (415) 947-8715 orColleen McKaughan, Associate Air Division Director at (520) 498-0118. Sincerely,

# L(::1~ Acting Regional Administrator Enclosures

cc: Benjamin H. Grumbles, Director, Arizona Department ofEnvironmental Quality Patrick Cunningham, Deputy Director, Arizona Department ofEnvironmental Quality Nancy Wrona, Director, Air Quality Division, Arizona Department ofEnvironmental Quality Don Gabrielson, Director, Pinal CountyAir Quality Control District Lawrence OdIe, Director, Maricopa County Air QualityDepartment Ursula Kramer, Director, Pima CountyDepartment ofEnvironmental Quality

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