Approval and Promulgation of Air Quality Implementation Plans; Texas; Revisions to the Ozone Attainment Plan for the Houston/Galveston/Brazoria Nonattainment Area

Résumé

EPA is approving revisions to the Texas State Implementation Plan (SIP) as it applies to the Houston/Galveston/Brazoria (HGB) ozone nonattainment area. These SIP revisions result from more recent information on ozone formation in the HGB area indicating that a combination of controls on nitrogen oxides (NO X ) and highly reactive volatile organic compounds (HRVOCs) should be more effective in reducing ozone than the measures in the previously approved 2001 HGB attainment demonstration plan which relied almost exclusively on the control of NO X . Approval of these revisions incorporates these changes into the federally approved SIP. The approved revisions include a 1-hour ozone standard attainment demonstration, motor vehicle emissions budgets, a demonstration that all reasonably available control measures have been adopted for the HGB area and revisions to satisfy the enforceable commitments contained in the previously approved SIP. These revisions present a new mix of controlled strategies in order to achieve attainment. These revisions include changes to the industrial NO X rules, reducing the stringency from a nominal 90 percent to 80 percent control and revisions to the Texas I