Air Quality Planning for Transportation Officials

SIP Deadlines and Attainment Dates

SIPs are required to be adopted by the State and submitted to EPA as legally enforceable plans. The CAA established the following attainment dates for ozone, carbon monoxide, and PM-10 nonattainment areas:

In practice however, actual submittals and approvals of SIPs do not always precisely follow the specific timetables established in the CAA. Therefore, there are some nonattainment areas, which still carry classifications that are well beyond their statutory attainment date, even though those areas may not be monitoring any violations of the standards. These timetables can be missed for a variety of reasons, such as:

• Additional time needed to resolve technical issues associated with air quality modeling;
• Negotiations among public officials, planners, and the public on how the emissions reductions should be allocated among stationary, area, and mobile sources;
• Actions required by State and local legislative bodies to adopt enforceable control measures;
• Negotiations and information exchanges between EPA and the State air agency over the adequacy of the SIP and its component parts (i.e., rather than taking an action to disapprove a submittal, EPA may try to work with the air agency to make the necessary changes to the submitted SIP so that it can be approved).