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Technology Transfer Network / NAAQS
Ozone Implementation

Finding of Significant Contribution and
Rulemakings for Certain States in the
Ozone Transport Assessment Group Region

Information provided for informational purposes onlyNote: EPA no longer updates this information, but it may be useful as a reference or resource.
for Purposes of Reducing Regional Transport of Ozone (" NOx SIP Call ")

On September 24, 1998, EPA finalized a rule (known as the NOx SIP Call) requiring 22 States and the District of Columbia to submit State implementation plans that address the regional transport of ground-level ozone. By improving air quality and reducing emissions of nitrogen oxides (a precursor to ozone formation known as NOx), the actions directed by these plans will decrease the transport of ozone across State boundaries in the eastern half of the United States. The rule requires emission reduction measures to be in place by May 1, 2003. The NOx SIP call builds upon analyses conducted by the Ozone Transport Assessment Group (OTAG). OTAG was a partnership between the EPA, the Environmental Council of the States and various industry and environmental groups which assessed the long-range transport of ozone and ozone precursors.

  Notice of Proposed Rulemaking

Supplemental Notice of Proposed Rulemaking

Notice of Final Rulemaking

Related Documents and Data




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