UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

REGION IX 

75 Hawthorne Street 

San Francisco, CA 94105·3901 

OFFICE OF THE 

OCT REGIONAL ADMINISTRATOR 1 4 2009 

The Honorable Jan Brewer 

Governor of Arizona 

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 of an initial 

designation of nonattainment for the 2006 24-hour national ambient air quality standard 

(NAAQS) for fine particles (PM25), a revised designation of nonattainment for the 1997 annual 

PM2.5NAAQS, and a revised designation of nonattainment for the 1987 24-hour PM IO NAAQS. 

These changes are necessary based upon violations of all 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 of recommendations for designations to EPA by letter 

from Janet Napolitano, Governor, dated December 19,2007. Last year, EPA notified you of its 

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 of 2008. Due to the
 

change of Administration, however, EPA did not complete the process at that time. Therefore, at
 

the request of the new Administration, EPA has reviewed the status of areas 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 of 2006­


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 may be 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 of counties immediately surrounding
 

Pinal County to determine whether any of these nearby counties contribute to the violation. EPA
 

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is therefore deferring the designations for these countiesl for the 2006 24-hour PM2.5NAAQS so 

that EPA can collect additional information sufficient to assess these areas before promulgating 

designations. We recognize that these are large geographical areas, and we recognize that the 

counties surrounding Pinal County are currently attaining the 2006 24-hour PM2.5 NAAQS. 

Looking at the counties surrounding Pinal County is only a starting point 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 should be balanced with a key purpose of designations, which is to identify those 

nearby contributing areas that should be included within a designated nonattainment area to 

ensure the development of an appropriate State Implementation Plan for the area. This is 

explained further in the Federal Register notice for final 24-hour PM2.5designations, at 

www.epa.gov/pmdesignations/2006standards/regs.htm#3. Factors that should be considered as 

the basis for nonattainment area boundaries are described in a guidance memorandum entitled 

"Area Designations 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 of our intended 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 PM2.5 NAAQS because this area was then 

meeting the standard. Unfortunately, the most recent 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 may be 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 of Pinal County, and any nearby areas that may be contributing to 

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 PM2.5 NAAQS. 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 area boundaries 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 may be contributing 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. 

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an appropriate starting point 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 10 NAAQS 

The most recent air quality monitoring data for PM IO, for the period 2006-2008, indicate 

that Pinal County is 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 may be 

contributing to the violations in Pinal County, as "nonattainment" for the 24-hour PM IO 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 of PM 10. The boundary for this NAAQS mayor may 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 PM2.5 NAAQS. 

We look forward to continuing to work with you and your staff to develop area
 

designations. EPA will evaluate your recommendations and will work with your staff to assure
 

that the final designations and boundaries for each of the NAAQS are appropriate, based on the
 

relevant facts and circumstances. After promulgation ofthe new designations for this area for
 

these NAAQS, EPA will likewise work with your staff to develop appropriate State
 

Implementation Plans to assure the public health protections intended by the standards. If you
 

have any questions, please do not hesitate to contact me. Your air quality staff may wish to
 

contact Deborah Jordan, Air Division Director at (415) 947-8715 or Colleen McKaughan,
 

Associate Air Division Director at (520) 498-0118.
 

Sincerely, 

L(::1~ Acting Regional Administrator 

Enclosures 

cc:	 Benjamin H. Grumbles, Director, Arizona Department of Environmental Quality
 

Patrick Cunningham, Deputy Director, Arizona Department of Environmental Quality
 

Nancy Wrona, Director, Air Quality Division, Arizona Department of Environmental
 

Quality 

Don Gabrielson, Director, Pinal County Air Quality Control District 

Lawrence OdIe, Director, Maricopa County Air Quality Department 

Ursula Kramer, Director, Pima County Department of Environmental Quality 

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