This action finalizes the residual risk and technology review (RTR) conducted for the Hydrochloric Acid (HCl) Production source category regulated under national emission standards for hazardous air pollutants (NESHAP). In addition, in this action we are finalizing amendments to add electronic reporting; address periods of startup, shutdown, and malfunction (SSM); and establish work practice standards for maintenance activities pursuant to the Clean Air Act (CAA). We are making no revisions to the numerical emission limits based on the risk analysis or technology review. Although these amendments are not anticipated to result in reductions in emissions of hazardous air pollutants (HAP), they will result in improved monitoring, compliance and implementation of the rule.