Texas Has Some of the Most Stringent Emission Regulations in the U.S.

The following strategies that have resulted in significant reductions in nitrogen oxides (NO_x) and volatile organic compounds (VOCs) over the past 10 years:

• The Mass Emission Cap and Trade program for NO_x in the Houston-Galveston-Brazoria (HGB) ozone nonattainment area—reduced the NO_x emissions cap for thousands of sources by more than 500 tons per day, overall about 80 percent (2002–08).
• A comprehensive suite of new rules adopted for the Dallas-Fort Worth (DFW) eight-hour ozone nonattainment area requiring NO_x reductions from cement kilns, power plants, industrial sites, stationary engines used in the oil and gas industry, and many other sources (March 2009–March 2010).
• Rules for enhanced monitoring and testing of flares, cooling towers, and other sources of highly reactive volatile organic compounds (HRVOCs) known to cause rapid formation of ozone (January 2006).
• Annual and short-term limits on HRVOC emissions for sources in Harris County (January 2007).
• New requirements for VOC storage tanks in the HGB area to address VOC emissions that were found using new technology like gas-imaging cameras that allow the operators to observe plumes of VOC emissions that would normally not be visible (January 2009).

Additional State Regulations

While not required by federal regulations, Texas has also adopted regional control strategies that required reductions from certain sources in counties outside the attainment areas. These controls help improve air quality in areas like DFW by reducing transport of pollution from outside the area.  Examples of such regional control strategies include:

• East and Central Texas Utility Rule (Senate Bill 7): Required NO_x and SO₂ reductions from grandfathered power plants in East Texas (2003–05).
• Regional Cement Kiln Rule: Required NO_x reductions from cement kilns in Bexar, Comal, Ellis, Hays, and McLennan counties (2003–05).
• East Texas Combustion Rule: Requires NO_x reductions from certain stationary gas-fired engines in 33 attainment counties east and southeast of DFW, primarily in the oil and gas industry (March 2010).