This action finalizes the residual risk and technology review (RTR) conducted for the Off-Site Waste and Recovery Operations (OSWRO) source category regulated under national emission standards for hazardous air pollutants (NESHAP). In addition, the Environmental Protection Agency (EPA) is finalizing amendments to correct and clarify regulatory provisions related to emissions during periods of startup, shutdown and malfunction (SSM); add requirements for reporting of performance testing through the Electronic Reporting Tool (ERT); revise the routine maintenance provisions; clarify provisions pertaining to open-ended valves and lines (OELs); add monitoring requirements for pressure relief devices (PRDs); clarify provisions for some performance test methods and procedures; and make several minor clarifications and corrections. The revisions to the final rule increase the level of emissions control and environmental protection provided by the OSWRO NESHAP.