National Emission Standards for Hazardous Air Pollutants for Source Categories; National Emission Standards for Hazardous Air Pollutants for Secondary Aluminum Production

This action proposes national emission standards for hazardous air pollutants (NESHAP) for new and existing sources at secondary aluminum production facilities. Hazardous air pollutants (HAPs) emitted by the facilities that would be regulated by this proposed rule include HAP organics, inorganic HAPs (hydrogen chloride, hydrogen fluoride, and chlorine), and particulate HAP metals. Some of these pollutants, including 2,3,7,8-tetrachlorodibenzo-p-dioxin, are considered to be known or suspected carcinogens and all can cause toxic effects following sufficient exposure. Emissions of other pollutants include particulate matter and volatile organic compounds. The standards are proposed under the authority of section 112(d) of the Clean Air Act (the Act) and are based on the Administrator's determination that secondary aluminum production plants are major sources of HAP emissions and emit several of the HAPs listed in section 112(b) of the Act from the various process operations found within the industry. The proposed NESHAP would reduce risks to public health and environment by requiring secondary aluminum production plants to meet emission standards reflecting application of the maximum available control technology (MACT). Secondary aluminum production plants that are area sources would be subject to limitations on emissions of dioxins and furans (D/F) only. Implementation of the proposed NESHAP would reduce emissions of HAPs and other pollutants by about 16,600 megagrams per year (Mg/yr) (18,300 tons per year (tpy)).