National Emission Standards for Hazardous Air Pollutants for Ferroalloys Production: Ferromanganese and Silicomanganese

This action finalizes national emission standards for hazardous air pollutants (NESHAP) for ferroalloys production: ferromanganese and silicomanganese. This rule was proposed under the title of ``national emission standards for hazardous air pollutants for ferroalloys production.'' The EPA changed the title of the final rule to reflect the specific ferroalloy produced (ferromanganese and silicomanganese) at the only existing source to be regulated. The EPA also has deleted the proposed applicability to ferrochromium production with this action and withdrawn the proposed rule for ferronickel production facilities. The EPA has identified ferromanganese and silicomanganese facilities as major sources of hazardous air pollutants (HAP) emissions of manganese. Manganese can adversely affect human health. The effects of chronic human exposure to environmental levels of manganese through inhalation include subtle but not insignificant effects on the central nervous system. These effects, reported in workers exposed to manganese, include slow visual reaction time, loss of eye-hand coordination, and imprecise hand movements caused by small tremors. The NESHAP requires affected sources to meet emission standards that reflect the application of maximum achievable control technology (MACT).