Stuart Spencer, Chief 

Air Division 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

REGION6 

1445 ROSS AVENUE, SUITE 1200 

DALLAS TX 75202-2733 

October 20, 2015 

Arkansas Department of Environmental Quality 

5301 Northshore Drive 

North Little Rock, AR 72118-5317 

Dear Mr. Spencer: 

Thank you for the recommendations regarding the attainment status of selected areas in Arkansas under 

the 2010 sulfur dioxide (S02) national ambient air quality standard (NAAQS) that your agency sent to 

us on September 11, 2015. As you know, we are subject to a March 2, 2015, court order directing us to 

promulgate S02 designations for these areas under section 107 of the Clean Air Act by July 2, 2016. 

Specifically, we are required to promulgate designations for these areas because they contain sources 

meeting the S02 emissions criteria identified in the consent decree. The information you provided on 

September 11 , 2015, will greatly help us meet this duty, and ensure protection of public health in 

Arkansas. 

In addition to the information you have provided, we have recently received modeling and related 

information from the Sierra Club that is relevant to a subset of the areas to be addressed by July 2, 2016. 

In your state, we have received information pertinent to the area near to the following power plants: 

White Bluff Steam Electric Station and Independence Steam Electric Station. We are enclosing a 

compact disc that contains this information. Please let us know if you have any questions about the 

information we have received or if you need any additional information. 

I am writing to solicit your review of the information that Sierra Club has provided, so that the EPA can 

base its designation decisions on the best available information. The Clean Air Act provides for 

designations to be developed through a partnership of state agencies and the EPA, however we also 

believe it is important to consider significant and relevant information that members of the public 

provide to us. Consistent with the structure of the Clean Air Act, we believe that the best first step in 

addressing this information would be for your agency to provide its review of this information. Since the 

Sierra Club's recommendation differs from your recommendation, we would welcome your commentary 

generally on the information as well as your detailed review of the elements of Sierra Club's analysis. 

To the extent practicable, we would appreciate quantitative comparisons of data used in Sierra Club's 

analysis compared to the data used in your analysis, to help us evaluate the elements of the two analyses. 

We would appreciate your review of Sierra Club's information by November 17, 2015. Your timely 

review would provide us valuable assistance in our review of your designation recommendations and 

development of our intended designations, which we are aiming to complete by the end of January 2016. 

We will then publish notice of our intended designations for public comment, and, as required by the 

Internet Address (URL) • http://www.epa.gov/region6 

Recycled/Recyclable • Printed with Vegetable Oil Based Inks on 100% Postconsumer, Process Chlorine Free Recycled Paper 
Clean Air Act, promulgate final designations no sooner than 120 days after giving you notice of them. 

Please contact me or James E. Grady of my staff at 2 14-665-6745 or at grady.james@epa.gov if you 

have any questions about this request. 

Enclosure: cd 

Sincerely, 

~4l i (/L )~ re~· Guy Donaldson 

Chief 

Air Planning Section