National Emission Standards for Hazardous Air Pollutants: Ferroalloys Production

This action sets forth the Environmental Protection Agency's (EPA's) final decision on the issues for which it announced reconsideration on July 12, 2016, that pertain to certain aspects of the June 30, 2015, final amendments for the Ferroalloys Production source category regulated under national emission standards for hazardous air pollutants (NESHAP). The EPA is amending the rule to allow existing facilities with positive pressure baghouses to perform visible emissions monitoring twice daily as an alternative to installing and operating bag leak detection systems (BLDS) to ensure the baghouses are operating properly. In addition, this final action explains that EPA is maintaining the requirement that facilities must use a digital camera opacity technique (DCOT) method to demonstrate compliance with opacity limits. However, this final action revises the rule such that it references the recently updated version of the DCOT method. In this action, the EPA also explains that no changes are being made regarding the rule provision that requires quarterly polycyclic aromatic hydrocarbons (PAH) emission testing for furnaces producing ferromanganese (FeMn) with an opportunity for facilities to request decreased compliance test frequency from their permitting authority after the first year. Furthermore, in this action, the EPA is denying the request for reconsideration of the PAH emission limits for both FeMn and silicomanganese (SiMn) production furnaces.