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Infrastructure SIP Requirements and Guidance

States are required to submit "infrastructure" SIPs under Section 110(a) of the Clean Air Act that implement, maintain, and enforce new or revised national ambient air quality standards (NAAQS) within 3 years of EPA issuing the standard.


Requirements for infrastructure SIPs are defined in the Clean Air Act sections listed below.

See full text of Section 110(a) (links to U.S. Code)

  • Section 110(a)(2)(A) Emission limits and other control measures
  • Section 110(a)(2)(B) Ambient air quality monitoring/data system
  • Section 110(a)(2)(C) Program for enforcement of control measures
  • Section 110(a)(2)(D)(i) - I Prong 1: Interstate transport - significant contribution
  • Section 110(a)(2)(D)(i) - I Prong 2: Interstate transport - interfere with maintenance
  • Section 110(a)(2)(D)(i) - II Prong 3: Interstate transport - prevention of significant deterioration
  • Section 110(a)(2)(D)(i) - II Prong 4: Interstate transport - protect visibility
  • Section 110(a)(2)(D)(ii) - Interstate and international pollution abatement
  • Section 110(a)(2)(E) Adequate authority and resources
  • Section 110(a)(2)(F) Stationary source monitoring system
  • Section 110(a)(2)(G) Emergency episodes
  • Section 110(a)(2)(H) Future SIP revisions
  • Section 110(a)(2)(J) Consultation with government officials; Public notification; PSD and visibility protection
  • Section 110(a)(2)(K) Air quality modeling/data
  • Section 110(a)(2)(L) Permitting fees
  • Section 110(a)(2)(M) Consultation/participation by affected local entities


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