Pursuant to the Federal Clean Air Act (CAA or Act), the Environmental Protection Agency (EPA) is proposing this action to address the voluntary remand of portions of a final rulemaking published in the Federal Register on January 5, 2016, addressing regional haze obligations for the first planning period in Texas and Oklahoma. Specifically, we are revisiting and again proposing disapproval of portions of the Texas Regional Haze State Implementation Plan (SIP) submission and portions of the Oklahoma Regional Haze SIP submission that relate to reasonable progress requirements for the first planning period from 2008 through 2018. We are also proposing to rescind the sulfur dioxide (SO<INF>2</INF>) emission limitations we promulgated as part of the Federal Implementation Plan (FIP) in the January 2016 Final Rule for 15 Texas electric generating units (EGUs) at eight facilities. We are proposing to determine that no additional controls are required for Texas or Oklahoma sources under these States' long-term strategies for making reasonable progress for the first planning period. We are leaving the portions of the Texas and Oklahoma Regional Haze SIPs that we approved in the January 2016 Final Rule in place and not reopening those determinations in this action.