The Honorable Greg Abbott 

Governor ofTexas 

Post Office Box I 2428 

Austin, Texas 78711 

Dear Governor Abbott: 

Thank you for your recommendations dated September 18, 201 5, on air quality designations for the state 

ofTexas for the 2010 revision to the primary National Ambient Air Quality Standard (NAAQS) for 

sulfur dioxide (S02). Reducing levels of S02 pollution is an important part of the U.S. Environmental 

Protection Agency's commitment to a clean, healthy environment. Exposure to S02 can cause a range of 

adverse health effects, including narrowing of the airways which can cause difficulty breathing and 

increased asthma symptoms. This letter is to notify you of the EPA's preliminary intentions regarding 

your recommended designations. 

On June 3, 201 0, the EPA strengthened the health-based or "primary" standard for S02 by establishing a 

standard for 1-hour average S02 concentrations at a level of 75 parts per billion. Within one year after a 

new or revised standard is established, the Clean Air Act requires the Governor of each state to submit 

to the EPA a list of all areas in the state, with recommendations for whether each area meets the 

standard. Through an interactive process, the EPA considers the recommendations and then promulgates 

designations for all areas across the country. On July 25,2013, the EPA designated 29 areas in 16 states 

as nonattainment, but did not at that time designate other areas. Pursuant to a March 2, 2015, courtordered schedule, I the EPA must complete the remaining so2 designations by three specific deadlines: 

July 2, 2016, December 31, 20 17, and December 31, 2020. 

This current round of designations, to be completed by July 2, 2016, addresses two groups ofareas: (1) 

areas that have newly monitored violations ofthe 2010 S02 NAAQS based on the most recent three 

calendar years of certified monitored ambient air quality data, and (2) areas that contain any stationary 

source that had not been announced as of March 2, 2015, for retirement and that according to the EPA's 

Air Markets Database emitted in 2012 either (i) more than 16,000 tons of S02 or (ii) more than 2,600 

tons of S02 with an annual average emission rate of at least 0.45 pounds of S02/mrnBTU. 

After carefully considering Texas' recommendations and other available technical information, the EPA 

intends to designate as nonattainment or unclassifiable/attainrnent the following areas, including the 

following counties or portions of counties: 

1 Sierra Club v. McCarthy, No. 3-13-cv-3953 (SI) (N.D. Cal. Mar. 2, 2015). 

This paper is printed with vegetable-oil-based inks and is 100-percent postconsumer recycled material, 

chlorine-free-processed and recyclable 
Texas (parts of)

 

Titus County, Texas (part)* 

Intended Unclassifiable/ Attainment 

Area 

Atascosa County, Texas 

Goliad County, Texas 

Lamb County, Texas 

Limestone County, Texas 

Robertson County, Texas 

(p ), and Panola County (p) 

Titus County (p) 

(p) indicates portion of county 

Intended Unclassifiable/ Attainment 

Area Counties 

Atascosa County 

Goliad County 

Lamb County 

Limestone County 

Robertson County . 

The asterisk(*) indicates the designation and boundary for the intended nonattainment areas represents a 

modification to the designation and boundary that you have recommended. 

Because the EPA has insufficient information to determine whether the following areas are meeting or 

not meeting the S02 NAAQS, the EPA intends to designate these areas as unclassifiable: 

Intended Unclassifiable Area 

McLennan County, Texas* 

Milam County, Texas* 

Potter County, Texas* 

Fort Bend County, Texas* 

Intended Unclassifiable Counties 

McLennan County 

Milam County 

Potter County 

Fort Bend County 

The asterisk (*) indicates the designation for these intended unclassifiable areas represents a 

modification to the designation that you have recommended. 

As noted above, we intend to designate Fort Bend County as unclassifiable. On January 25, 2016, the 

EPA received a revised modeling submittal from industry for the area surrounding the W.A. Parish 

Electric Generating Station located in Fort Bend County, Texas. The EPA's review of this latest 

modeling is currently underway. Due to the date of receipt of the latest modeling from industry relative 
designation decisions. If your state has additional information that the EPA should consider prior to 

finalizing these designations, please submit it to us by April 19, 2016. \Ve also will be publishing a 

notice in the Federal Register announcing a 30-day period for the public to provide input on the EPA's 

intended designation decisions. We will promulgate the designations for these areas by July 2, 2016. We 

will designate all other previously undesignated areas in the state on a schedule consistent with the 

prescribed timing of the court order, i.e., by December 31, 2017, or December 31, 2020. 

We look forward to a continued dialogue with you and your staff as we work together to complete the 

area designations and implement the 2010 primary S02 standard. For additional information regarding 

designations under the S02 standard, please visit our website at www.epa.gov/so2designations. Should 

you have any questions, please do not hesitate to call me, or have your staff contact Mr. Guy Donaldson 

of my staff at (214) 665-7242, or via email at Donaldson.guy@epa.gov. 

Enclosure 

cc: Richard A Hyde, P.E. 

Executive Director, Texas Commission on Environmental Quality 

Steve Hagle, P.E. 

Deputy Director, Office of Air, Texas Commission on Environmental Quality