Pursuant to the Federal Clean Air Act (CAA or the Act), the Environmental Protection Agency (EPA) is approving the CAA section 111(d) state plan submitted by the State of Arkansas for sources subject to the Municipal Solid Waste (MSW) Landfills Emission Guidelines (EG). The Arkansas MSW landfills plan was submitted to fulfill the state's obligations under CAA section 111(d) to implement and enforce the requirements under the MSW Landfills EG. The EPA is approving the state plan and amending the agency regulations in accordance with the requirements of the CAA.