The Environmental Protection Agency (EPA) is approving a State Implementation Plan (SIP) revision submitted by the State of Connecticut. This revision approves into the Connecticut SIP state regulations that apply restrictions on emissions of criteria pollutants for which EPA has established National Ambient Air Quality Standards. Separately, we are also approving Connecticut regulations that apply restrictions on emissions of hazardous air pollutants (HAPs). The Connecticut regulations impose legally and practicably enforceable emissions limitations restricting eligible sources' actual and potential emissions below major stationary source thresholds, if a source chooses to be covered by the regulations. Such restrictions generally allow eligible sources to avoid having to comply with reasonably available control technology (RACT) that would otherwise apply to major stationary sources, title V operating permit requirements, or other requirements that apply only to major stationary sources. This action is being taken under the Clean Air Act.