40 CFR § 440.10
Applicability; description of the iron ore subcategory
June 9, 2020
The provisions of this subpart A are applicable to discharges from (a) mines operated to obtain iron ore, regardless of the type of ore or its mode of occurrence; (b) mills beneficiating iron ores by physical (magnetic and nonmagnetic) and/or chemical separation; and (c) mills beneficiating iron ores by magnetic and physical separation in the Mesabi Range.