EPA is approving State Implementation Plan (SIP) revisions submitted by the Connecticut Department of Environmental Protection (CT, or DEP). This action consists of approving regulations in CT which are part of a regional nitrogen oxide (NO<INF>X</INF>) reduction program designed to reduce stationary source NO<INF>X</INF> emissions during the ozone season in the Ozone Transport Region (OTR) of the northeastern United States. Section 184(a) of the Clean Air Act defines an ozone transport region in the northeastern United States composed of the States of Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, and the Consolidated Metropolitan Statistical Area that includes the District of Columbia. Additionally, this action involves the approval of four source specific NO<INF>X</INF> trading orders which allow specific units at major stationary sources to meet reasonably available control technology (RACT) requirements through the use of emission reduction credits. These SIP revisions were submitted pursuant to section 110 of the Clean Air Act (CAA).