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Air Quality



On October 27, 1998, the United States Environmental Protection Agency (EPA) published a final rule titled, "Finding of Significant Contribution and Rulemaking for Certain States in the Ozone Transport Assessment Group Region for Purposes of Reducing Regional Transport of Ozone." This rule, also known as the NOX SIP Call, requires South Carolina and certain other states to limit the summertime emissions of oxides of nitrogen (NOX) which are one of the precursors of ozone pollution. EPA has stated in the rule that sources in these states emit NOX in amounts that significantly contribute to nonattainment of the 1-hour National Ambient Air Quality Standard (NAAQS) for ozone in one or more down-wind states. The NOX SIP Call required reductions of summertime emissions of NOX in South Carolina and requires the Department to submit a revision to the South Carolina State Implementation Plan (SIP) that identifies measures necessary to achieve these reductions. The Department submitted a SIP revision to comply with the requirements of the NOX SIP Call on May 28, 2002. EPA published a final rule in the Federal Register approving this revision on June 28, 2002 (67 FR 43546).

Under the NOX SIP Call, EPA set up the NOX Budget Trading Program, which capped NOX emissions of and set up a market for facilities to trade emissions credits. This program ended at the end of 2008, and EPA replaced it with trading programs under the Clean Air Interstate Rule (CAIR).

All documents linked below are in pdf format.

For more information please contact the Bureau of Air Quality at (803) 898-4123 or by email.