Approval and Promulgation of Implementation Plans(SIP); Texas: 1990 Base Year Emissions Inventories, 15% Rate of Progress Plans, Contingency Plans, and Motor Vehicle Emission Budgets

In this action, the EPA is granting conditional interim approval of the 15% Rate-of-Progress (ROP) Plans and associated Motor Vehicle Emissions Budgets (MVEB) for the Dallas/Fort Worth, El Paso and Houston/Galveston ozone nonattainment areas. In addition, EPA is fully approving revisions to the 1990 base year emissions inventories and the contingency plans for the three areas. The 15% ROP Plans and MVEB's are receiving conditional interim approval, instead of full approval, because they rely on emission reductions from the Texas Inspection and Maintenance (I/M) Program which received final conditional interim approval on July 11, 1997 (62 FR 37138). This action will aid in ensuring the attainment of the National Ambient Air Quality Standard (NAAQS) for ozone as required by the Clean Air Act (Act), as amended in 1990.