Clean Air Act Redesignation Substitute for the Dallas-Fort Worth 1-Hour Ozone and 1997 8-Hour Ozone Nonattainment Areas; Texas

The Environmental Protection Agency (EPA) is proposing to approve a redesignation substitute and make a finding of attainment for both the 1-hour ozone and the 1997 8-hour ozone National Ambient Air Quality Standards (NAAQS) for the Dallas-Fort Worth nonattainment area (DFW area). The redesignation substitute demonstration states that the area has attained both the revoked 1-hour ozone and the revoked 1997 8- hour ozone NAAQS due to permanent and enforceable emission reductions, and that it will maintain those NAAQS for ten years from the date of the EPA's approval of this demonstration. Final approval of the redesignation substitute will result in the area no longer being subject to any remaining applicable anti-backsliding requirements and the nonattainment new source review (NNSR) requirements associated with the revoked NAAQS. In general, final approval of the redesignation substitute would allow Texas to seek to revise the Texas SIP for the area to remove anti-backsliding measures from the active portion of its SIP if it can demonstrate, pursuant to the Clean Air Act (CAA) section 110(1), that such revision would not interfere with attainment or maintenance of any applicable NAAQS, or any other requirement of the CAA. However, the EPA believes that in this instance, Texas does not need to revise its SIP to alter certain provisions for NNSR effective in the DFW area.