National Emission Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing Industry

On June 14, 1999, under the authority of section 112 of the Clean Air Act (CAA), the EPA promulgated national emission standards for hazardous air pollutants (NESHAP) for new and existing sources in the portland cement manufacturing industry. On December 15, 2000, the United States Court of Appeals for the District of Columbia Circuit (DC Circuit) remanded parts of the NESHAP for the portland cement manufacturing industry to EPA to consider, among other things, setting maximum achievable control technology (MACT) floor standards for hydrogen chloride (HCl), mercury, and total hydrocarbons (THC), and beyond-the-floor standards for metal hazardous air pollutants (HAP). This action provides EPA's proposed rule amendments in response to those aspects of the court's remand.