The Environmental Protection Agency (EPA) is approving a Tribal implementation plan (TIP) submitted by the Swinomish Indian Tribal Community (SITC or the Tribe). The SITC TIP regulates open burning practices and establishes a Tribal regulatory program applicable to all persons within the exterior boundaries of the Swinomish Reservation (Reservation). The SITC TIP was submitted to the EPA on June 28, 2012, and supplementary submittals were received on September 24, 2013, November 18, 2013, and January 28, 2014. This action makes the approved portions of the SITC TIP federally enforceable under the Clean Air Act (CAA). Upon the effective date of this action, the SITC TIP will replace the Federal Implementation Plan (FIP) provisions that regulate open burning within the exterior boundaries of the Reservation.