This action finalizes the residual risk and technology review (RTR) conducted for the Integrated Iron and Steel Manufacturing Facilities source category regulated under national emission standards for hazardous air pollutants (NESHAP). The Agency found that risks due to emissions of air toxics from this source category are acceptable and that the current NESHAP provides an ample margin of safety to protect public health. Under the technology review, we found no developments in practices, processes, or control technologies that necessitate revision of the standards. In addition, we are taking final action to establish emission standards for mercury in response to a 2004 administrative petition for reconsideration which minimizes emissions by limiting the amount of mercury per ton of metal scrap used. We also are removing exemptions for periods of startup, shutdown, and malfunction (SSM) consistent with a 2008 court decision, and clarifying that the emissions standards apply at all times; adding electronic reporting of performance test results and compliance reports; and making minor corrections and clarifications for a few other rule provisions.