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Ground-level Ozone Pollution

Development of Specific Elements for Each of the Major SIP Types

Infrastructure SIP

An infrastructure SIP, or i-SIP, is a requirement for all states, regardless of designation. Even areas in attainment must demonstrate what controls they will continue to use and regulate in order to remain in attainment.

Nonattainment New Source Review SIP

Nonattainment area SIP, a.k.a. attainment demonstration SIP

Ozone Transport Region (OTR) SIP

  • New source review (NSR) program.
    • NSR offset ratio 1.15:1
    • major source threshold 50 tons per year (tpy) for VOC
    • major source threshold 100 tons per year (tpy) for NOx
  • Major source volatile organic compounds/nitrogen oxides (VOC/NOx) reasonably available control technology (RACT).  See 184(b)(1)(B): Plan provisions for States in Ozone Transport Regions
  • All control technique guidelines (CTGs) reasonably available control technology (RACT). See CTGs 
  • Enhanced emissions inspection and maintenance (I/M) program.

For more information, see 40 CFR 51.1116: Requirements for an Ozone Transport Region

Interstate transport SIP

  • Interstate Air Pollution Transport: upwind transport of pollutants across state borders makes it difficult for downwind states to meet health-based air quality standards for ozone.

Redesignation SIP, or maintenance SIP