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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION IX

Ms. Sue Kidd, Director Corporate Environmental Arizona Public Service P.O. Box 53999 Phoenix, Arizona 85072
Dear Ms. Kidd: 75 Hawthorne Street San Francisco, CA 94105-3901 

## JUL 2 6 2012

Thank you for your interest in Arizona's plan to address regional haze in protected national parks and wilderness areas as required under the Clean AirAct (CAA). I am responding to your recent letter requesting an extension ofthe public commentperiod and additional hearings.
We agree to extend the deadline for public comment and increase the number ofpublic hearings to provide ample opportunity for review and comment on the regional haze Federal Implementation Plan (FIP) regarding three powerplants in Arizona (Apache Generating Station, ChollaPowerPlant and Coronado Generating Station.) Weplan to extend the public commentperiod bytwo weeks, for a total of60 days, ending on September 18,2012. We also plan to conduct two additional public hearings, one ofwhich will beheld in northern Arizona (Holbrook), and one in southern Arizona (Benson). These are scheduled for August 14 and 15, 2012, respectively. These two hearings are in addition to the public hearing in Phoenix onJuly 31, 2012. We will carefully and thoroughlyreview comments, including any additional technical information, submitted during the public commentperiodpriorto making our final determination.
As background, underthe Regional Haze Rule, Arizona was required to submit a Regional Haze State Implementation Plan (SIP) in December 2007. InJanuary 2009, well after the CAA deadline for such action, we made a formal finding thatArizonahad not submitted a complete Regional Haze SIP. That finding started a two-year clockthat could be stopped onlybyour approval ofa SIP orpromulgation of a FIP. InJanuary 2011, wereceived a notice ofintentto sue followed by a lawsuit covering dozens of states, including Arizona, for which we had not approved a Regional Haze SIP orpromulgated a Regional Haze FIP under the CAA. Shortlythereafter, in February 2011, Arizona submitted a new Regional Haze SIP. Submittal ofthis plan, however, had no effect on the EPA's legal obligation to promulgate a Regional Haze FIP, unless the EPA was able to approve fully Arizona's Regional Haze SIP.
After lengthy and complex negotiations involving deadlines for numerous states, the mostrecent revision to the consent decree requires us to take actions on Arizona's SIP, or adopt a FIP, in two separate sets ofnotices. The final action date for the three powerplants in our current proposal is November 15,2012. The final action for the remainder ofArizona's SIP is July 15, 2013. These dates for us to act on Arizona's SIP are among the latest in the consent decree. Accordingly, on July 20, 2012, we proposed a partial approval and partial disapproval ofArizona's Regional Haze SIP with respect to its determination ofBestAvailable Retrofit Technology (BART) to

Pri11ted on Recvcled Papercontrol emissions from eightunits at

### three electric generating stations: Apache Generating Station, Cholla PowerPlant and Coronado Generating Station. Wehave proposed to approve the State's determination thatthese sources are subjectto BART, andto approve the emissions limits for sulfur dioxide (S(h) andparticulate matter (PM10) at all the units. We also have proposed to disapprove the BART emissions limits for nitrogen oxides (NOx) at most ofthe units. As a remedywe have proposed a FIP containingnew emissions limits for NOx as well as associated compliance requirements. This proposal.was published inthe Federal Register on July 

### 20,2012 and is available at: http:ljwww.epa.gov/region9/air/actions/az.html#all.
We are committedto working with Arizona on its regional haze plan. Priorto our July 

### 20,2012 proposal, EPA worked with Arizona, the affected utilities, the National Park Service, the environmental litigants, and others to gather information useful inpreparing ourproposal. EPA provided a prepublication version ofthe proposal thatwas published in the Federal Register to various parties, including the State, on July

### 2, 2012. States are entitled to deference to their reasoned decisions when consistent with the CAA and the Regional Haze Rule. However, we cannot give deference to state decisions ifwe find thatthe state's analysis does not complywith the regional haze requirements. Inthis case, where wehave proposed a FIP, we are committedto continuing to workwith the State ofArizona on approvable revisions to its SIP. When an approvable regional haze SIP revision is submitted to the EPA and approved, we will withdraw ourFIP. Again, thank you for your letter. Ifyou have further questions, please contact me oryour staffmay call Colleen McKaughan, Associate Director at 

### 520-498-0118. Sincerely,

# ;i;JJ-~ Director, Air Division