The Environmental Protection Agency (EPA) is approving a revision to the Minnesota sulfur dioxide (SO<INF>2</INF>) State Implementation Plan (SIP) for the Flint Hills Resources, LLC Pine Bend Refinery (FHR) as submitted on May 1, 2015. The revision will consolidate existing permanent and enforceable SO<INF>2</INF> SIP conditions into the facility's joint Title I/Title V SIP document. This action highlights process modifications necessary to meet EPA's Tier 3 gasoline sulfur standards; a comprehensive monitoring strategy to better quantify SO<INF>2</INF> emissions from fuel gas-fired emission units; a new restrictive flaring procedure for refinery process units, and other updates and administrative changes. This revision results in a modeled reduction in SO<INF>2</INF> emissions from FHR and modeled SO<INF>2</INF> ambient air concentrations less than half of the national ambient air quality standards (NAAQS).